Номер 2, страница 17, часть 3 - гдз по физике 9 класс рабочая тетрадь Грачев, Погожев

Авторы: Грачев А. В., Погожев В. А., Боков П. Ю., Вишнякова Е. А.

Тип: рабочая тетрадь

Издательство: Просвещение

Год издания: 2021 - 2026

Часть: 3

Цвет обложки: синий

ISBN: 978-5-09-098826-1 (ч.1) 978-5-09-098880-3 (ч.2) 978-5-09-098881-0 (ч.3)

Часть 3. Глава 8. Оптика. Параграф 40. Закон прямолинейного распространения света - номер 2, страница 17.

App\Models\Task {#1030 // resources/views/models/task/default.blade.php
  #connection: "mysql"
  #table: "tasks"
  #primaryKey: "id"
  #keyType: "int"
  +incrementing: true
  #with: []
  #withCount: []
  +preventsLazyLoading: false
  #perPage: 15
  +exists: true
  +wasRecentlyCreated: false
  #escapeWhenCastingToString: false
  #attributes: array:24 [
    "id" => 1435207
    "created_at" => "2026-04-10 13:58:26"
    "updated_at" => null
    "field_page_start" => "17"
    "field_page_end" => null
    "field_url" => "/9-klass/fizika/grachev-rabochaya-tetrad/40-2"
    "field_display_title" => "2"
    "field_outside_task" => null
    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1037
      #items: array:1 [
        0 => App\Models\Term {#1036
          #connection: "mysql"
          #table: "terms"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: false
          #with: []
          #withCount: []
          +preventsLazyLoading: false
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          +exists: true
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          #escapeWhenCastingToString: false
          #attributes: array:6 [
            "id" => 26
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "name" => "номер"
            "field_cases" => array:6 [
              "field_accusative_case" => "номер"
              "field_creative_case" => "номером"
              "field_dative_case" => "номеру"
              "field_genitive_case" => "номера"
              "field_nominative_case" => "номер"
              "field_prepositional_case" => "номере"
            ]
            "field_short_name" => ""
          ]
          #original: array:6 [
            "id" => 26
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "name" => "номер"
            "field_cases" => array:6 [
              "field_accusative_case" => "номер"
              "field_creative_case" => "номером"
              "field_dative_case" => "номеру"
              "field_genitive_case" => "номера"
              "field_nominative_case" => "номер"
              "field_prepositional_case" => "номере"
            ]
            "field_short_name" => ""
          ]
          #changes: []
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          #attributeCastCache: []
          #dateFormat: null
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          #dispatchesEvents: []
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          #touches: []
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          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
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      ]
      #escapeWhenCastingToString: false
    }
    "field_metatags_title" => null
    "field_metatags_description" => null
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    "field_description_bottom" => null
    "field_match" => null
    "breadcrumbs" => []
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      #items: []
      #escapeWhenCastingToString: false
    }
    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1076
      #items: array:1 [
        0 => App\Models\Branch {#1034
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
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          +exists: true
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          #escapeWhenCastingToString: false
          #attributes: array:24 [
            "id" => 1434847
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => null
            "field_branch_order" => "3"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1039
              #items: array:1 [
                0 => App\Models\Term {#1038
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
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                  +exists: true
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                  #escapeWhenCastingToString: false
                  #attributes: array:7 [
                    "id" => 31
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Часть"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Часть"
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                      "field_dative_case" => "Части"
                      "field_genitive_case" => "Части"
                      "field_nominative_case" => "Часть"
                      "field_prepositional_case" => "Части"
                    ]
                    "field_page_check_not_needed" => "1"
                    "field_short_name" => "ч."
                  ]
                  #original: array:7 [
                    "id" => 31
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Часть"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Часть"
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                      "field_nominative_case" => "Часть"
                      "field_prepositional_case" => "Части"
                    ]
                    "field_page_check_not_needed" => "1"
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                  ]
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                    0 => "*"
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              ]
              #escapeWhenCastingToString: false
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            "field_navigation_title" => null
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            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1040
              #items: array:1 [
                0 => App\Models\Book {#1041
                  #connection: "mysql"
                  #table: "books"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
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                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:50 [
                    "id" => 1203
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1042
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1044
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1046
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1048
                      #items: array:4 [ …4]
                      #escapeWhenCastingToString: false
                    }
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1053
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1054
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1056
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1058
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1060
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1061
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1062
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1063
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_publication_number" => "6"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1065
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1067
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2021"
                    "field_publication_year_until" => null
                    "field_part" => "1, 2, 3"
                    "field_part_writing" => "Часть"
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебное издание"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
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                    "field_isbn" => "978-5-09-098826-1 (ч.1) 978-5-09-098880-3 (ч.2) 978-5-09-098881-0 (ч.3)"
                    "field_cover" => array:3 [
                      0 => "/media/fizika_09/grachev-rt/covers/cover1.webp?ts=1759003248"
                      1 => "/media/fizika_09/grachev-rt/covers/cover2.webp?ts=1759003248"
                      2 => "/media/fizika_09/grachev-rt/covers/cover3.webp?ts=1759003248"
                    ]
                    "field_cover_alts" => array:3 [
                      0 => ""
                      1 => ""
                      2 => ""
                    ]
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                      0 => array:4 [ …4]
                      1 => array:4 [ …4]
                      2 => array:4 [ …4]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1068
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1069
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1070
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/9-klass/fizika/grachev-rabochaya-tetrad"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1071
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_metatags_title" => null
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                      "class_subject" => 493
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                  #original: array:50 [
                    "id" => 1203
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                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
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                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1042}
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                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1053}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1054}
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                    "field_city" => Illuminate\Database\Eloquent\Collection {#1058}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1060}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1061}
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                    "field_cover" => array:3 [
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                      1 => array:4 [ …4]
                      2 => array:4 [ …4]
                    ]
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                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1068}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1069}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1070}
                    "field_url" => "/9-klass/fizika/grachev-rabochaya-tetrad"
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            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1073
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                            "created_at" => "2026-04-10 13:58:26"
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                            "field_abbreviated_name" => null
                            "field_cases" => array:6 [
                              "field_accusative_case" => "физику"
                              "field_creative_case" => "физикой"
                              "field_dative_case" => "физике"
                              "field_genitive_case" => "физики"
                              "field_nominative_case" => "физика"
                              "field_prepositional_case" => "физике"
                            ]
                            "field_foreign_lang_name" => null
                            "field_short_name" => null
                            "field_subject_type" => "technical_subject"
                            "field_translit" => "fizika"
                          ]
                          #original: array:10 [
                            "id" => 6493
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Физика"
                            "field_abbreviated_name" => null
                            "field_cases" => array:6 [
                              "field_accusative_case" => "физику"
                              "field_creative_case" => "физикой"
                              "field_dative_case" => "физике"
                              "field_genitive_case" => "физики"
                              "field_nominative_case" => "физика"
                              "field_prepositional_case" => "физике"
                            ]
                            "field_foreign_lang_name" => null
                            "field_short_name" => null
                            "field_subject_type" => "technical_subject"
                            "field_translit" => "fizika"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1171
                      #items: array:1 [
                        0 => App\Models\Term {#1172
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 5458
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "9"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "девятый"
                              "field_creative_case" => "девятым"
                              "field_dative_case" => "девятому"
                              "field_genitive_case" => "девятого"
                              "field_nominative_case" => "девятый"
                              "field_prepositional_case" => "девятом"
                            ]
                            "field_translit" => "devjatyj"
                          ]
                          #original: array:6 [
                            "id" => 5458
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "9"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "девятый"
                              "field_creative_case" => "девятым"
                              "field_dative_case" => "девятому"
                              "field_genitive_case" => "девятого"
                              "field_nominative_case" => "девятый"
                              "field_prepositional_case" => "девятом"
                            ]
                            "field_translit" => "devjatyj"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1173
                      #items: array:1 [
                        0 => App\Models\Term {#1174
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 5153
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Просвещение"
                            "field_cases" => null
                            "field_translit" => "prosveschenie"
                          ]
                          #original: array:6 [
                            "id" => 5153
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Просвещение"
                            "field_cases" => null
                            "field_translit" => "prosveschenie"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1175
                      #items: array:4 [
                        0 => App\Models\Term {#1176
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:12 [
                            "id" => 4180
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Грачев"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Александр"
                            "field_patronymic" => "Васильевич"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 4180
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Грачев"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Александр"
                            "field_patronymic" => "Васильевич"
                            "field_surname_rp" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                        1 => App\Models\Term {#1177
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:12 [
                            "id" => 5484
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Погожев"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Владимир"
                            "field_patronymic" => "Александрович"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 5484
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Погожев"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Владимир"
                            "field_patronymic" => "Александрович"
                            "field_surname_rp" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                        2 => App\Models\Term {#1178
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:12 [
                            "id" => 3888
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Боков"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Павел"
                            "field_patronymic" => "Юрьевич"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 3888
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Боков"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Павел"
                            "field_patronymic" => "Юрьевич"
                            "field_surname_rp" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                        3 => App\Models\Term {#1179
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:12 [
                            "id" => 4007
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Вишнякова"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Екатерина"
                            "field_patronymic" => "Анатольевна"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 4007
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Вишнякова"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Екатерина"
                            "field_patronymic" => "Анатольевна"
                            "field_surname_rp" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1180
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1181
                      #items: array:1 [
                        0 => App\Models\Term {#1182
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:10 [
                            "id" => 6736
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "рабочая тетрадь"
                            "field_book_type_foreign" => null
                            "field_cases" => array:6 [
                              "field_accusative_case" => "рабочую тетрадь"
                              "field_creative_case" => "рабочей тетрадью"
                              "field_dative_case" => "рабочей тетради"
                              "field_genitive_case" => "рабочей тетради"
                              "field_nominative_case" => "рабочая тетрадь"
                              "field_prepositional_case" => "рабочей тетради"
                            ]
                            "field_plural_form" => "рабочие тетради"
                            "field_short_name" => "рт"
                            "field_short_name_foreign" => null
                            "field_translit" => "rabochaya tetrad"
                          ]
                          #original: array:10 [
                            "id" => 6736
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "рабочая тетрадь"
                            "field_book_type_foreign" => null
                            "field_cases" => array:6 [
                              "field_accusative_case" => "рабочую тетрадь"
                              "field_creative_case" => "рабочей тетрадью"
                              "field_dative_case" => "рабочей тетради"
                              "field_genitive_case" => "рабочей тетради"
                              "field_nominative_case" => "рабочая тетрадь"
                              "field_prepositional_case" => "рабочей тетради"
                            ]
                            "field_plural_form" => "рабочие тетради"
                            "field_short_name" => "рт"
                            "field_short_name_foreign" => null
                            "field_translit" => "rabochaya tetrad"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1183
                      #items: array:1 [
                        0 => App\Models\Term {#1184
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 9
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Россия"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "rossiya"
                          ]
                          #original: array:6 [
                            "id" => 9
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Россия"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "rossiya"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1185
                      #items: array:1 [
                        0 => App\Models\Term {#1186
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "moskva"
                          ]
                          #original: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "moskva"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1187
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1188
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1189
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1190
                      #items: array:1 [
                        0 => App\Models\Term {#1191
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:10 [
                            "id" => 6706
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "ФГОС (старый)"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                               …1
                            ]
                            "field_color" => null
                            "field_end_year" => "2022"
                            "field_start_year" => "2019"
                            "field_translit" => "fgos-old"
                            "field_type" => null
                          ]
                          #original: array:10 [
                            "id" => 6706
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "ФГОС (старый)"
                            "field_cases" => array:6 [ …6]
                            "field_color" => null
                            "field_end_year" => "2022"
                            "field_start_year" => "2019"
                            "field_translit" => "fgos-old"
                            "field_type" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_publication_number" => "6"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1192
                      #items: array:1 [
                        0 => App\Models\Term {#1193
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 33
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "стереотипное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "stereotipnoe"
                          ]
                          #original: array:6 [
                            "id" => 33
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "стереотипное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "stereotipnoe"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1194
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2021"
                    "field_publication_year_until" => null
                    "field_part" => "1, 2, 3"
                    "field_part_writing" => "Часть"
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебное издание"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "594"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_09/grachev-rt/"
                    "field_isbn" => "978-5-09-098826-1 (ч.1) 978-5-09-098880-3 (ч.2) 978-5-09-098881-0 (ч.3)"
                    "field_cover" => array:3 [
                      0 => "/media/fizika_09/grachev-rt/covers/cover1.webp?ts=1759003248"
                      1 => "/media/fizika_09/grachev-rt/covers/cover2.webp?ts=1759003248"
                      2 => "/media/fizika_09/grachev-rt/covers/cover3.webp?ts=1759003248"
                    ]
                    "field_cover_alts" => array:3 [
                      0 => ""
                      1 => ""
                      2 => ""
                    ]
                    "field_covers" => array:3 [
                      0 => array:4 [
                        "path" => "/media/fizika_09/grachev-rt/covers/cover1.webp?ts=1759003248"
                        "alt" => ""
                        "width" => "2293"
                        "height" => "2989"
                      ]
                      1 => array:4 [
                        "path" => "/media/fizika_09/grachev-rt/covers/cover2.webp?ts=1759003248"
                        "alt" => ""
                        "width" => "2265"
                        "height" => "3003"
                      ]
                      2 => array:4 [
                        "path" => "/media/fizika_09/grachev-rt/covers/cover3.webp?ts=1759003248"
                        "alt" => ""
                        "width" => "2241"
                        "height" => "2999"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1195
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1196
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1197
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/9-klass/fizika/grachev-rabochaya-tetrad"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1198
                      #items: array:1 [
                        0 => App\Models\Term {#1199
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 49
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "синий"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "siniy"
                          ]
                          #original: array:6 [
                            "id" => 49
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "синий"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "siniy"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 380
                      "subject" => 556
                      "class_subject" => 493
                    ]
                  ]
                  #original: array:50 [
                    "id" => 1203
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1170}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1171}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1173}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1175}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1180}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1181}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1183}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1185}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1187}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1188}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1189}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1190}
                    "field_publication_number" => "6"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1192}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1194}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2021"
                    "field_publication_year_until" => null
                    "field_part" => "1, 2, 3"
                    "field_part_writing" => "Часть"
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебное издание"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "594"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_09/grachev-rt/"
                    "field_isbn" => "978-5-09-098826-1 (ч.1) 978-5-09-098880-3 (ч.2) 978-5-09-098881-0 (ч.3)"
                    "field_cover" => array:3 [
                      0 => "/media/fizika_09/grachev-rt/covers/cover1.webp?ts=1759003248"
                      1 => "/media/fizika_09/grachev-rt/covers/cover2.webp?ts=1759003248"
                      2 => "/media/fizika_09/grachev-rt/covers/cover3.webp?ts=1759003248"
                    ]
                    "field_cover_alts" => array:3 [
                      0 => ""
                      1 => ""
                      2 => ""
                    ]
                    "field_covers" => array:3 [
                      0 => array:4 [
                        "path" => "/media/fizika_09/grachev-rt/covers/cover1.webp?ts=1759003248"
                        "alt" => ""
                        "width" => "2293"
                        "height" => "2989"
                      ]
                      1 => array:4 [
                        "path" => "/media/fizika_09/grachev-rt/covers/cover2.webp?ts=1759003248"
                        "alt" => ""
                        "width" => "2265"
                        "height" => "3003"
                      ]
                      2 => array:4 [
                        "path" => "/media/fizika_09/grachev-rt/covers/cover3.webp?ts=1759003248"
                        "alt" => ""
                        "width" => "2241"
                        "height" => "2999"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1195}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1196}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1197}
                    "field_url" => "/9-klass/fizika/grachev-rabochaya-tetrad"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1198}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 380
                      "subject" => 556
                      "class_subject" => 493
                    ]
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1200
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1434847
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => null
            "field_branch_order" => "3"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1169}
            "field_page_start" => "3"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1202}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1200}
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        1 => App\Models\Branch {#1201
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:24 [
            "id" => 1434852
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Оптика"
            "field_branch_order" => "8"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1206
              #items: array:1 [
                0 => App\Models\Term {#1203
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:7 [
                    "id" => 29
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Глава"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Главу"
                      "field_creative_case" => "Главой"
                      "field_dative_case" => "Главе"
                      "field_genitive_case" => "Главы"
                      "field_nominative_case" => "Глава"
                      "field_prepositional_case" => "Главе"
                    ]
                    "field_page_check_not_needed" => null
                    "field_short_name" => null
                  ]
                  #original: array:7 [
                    "id" => 29
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Глава"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Главу"
                      "field_creative_case" => "Главой"
                      "field_dative_case" => "Главе"
                      "field_genitive_case" => "Главы"
                      "field_nominative_case" => "Глава"
                      "field_prepositional_case" => "Главе"
                    ]
                    "field_page_check_not_needed" => null
                    "field_short_name" => null
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "15"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1205
              #items: array:1 [
                0 => App\Models\Book {#1168}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1204
              #items: array:1 [
                0 => App\Models\Branch {#1034}
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1434852
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Оптика"
            "field_branch_order" => "8"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1206}
            "field_page_start" => "15"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1205}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1204}
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        2 => App\Models\Branch {#1207
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:24 [
            "id" => 1434854
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Закон прямолинейного распространения света"
            "field_branch_order" => "40"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1211
              #items: array:1 [
                0 => App\Models\Term {#1208
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:7 [
                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Параграф"
                      "field_creative_case" => "Параграфом"
                      "field_dative_case" => "Параграфу"
                      "field_genitive_case" => "Параграфа"
                      "field_nominative_case" => "Параграф"
                      "field_prepositional_case" => "Параграфе"
                    ]
                    "field_page_check_not_needed" => null
                    "field_short_name" => "§"
                  ]
                  #original: array:7 [
                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Параграф"
                      "field_creative_case" => "Параграфом"
                      "field_dative_case" => "Параграфу"
                      "field_genitive_case" => "Параграфа"
                      "field_nominative_case" => "Параграф"
                      "field_prepositional_case" => "Параграфе"
                    ]
                    "field_page_check_not_needed" => null
                    "field_short_name" => "§"
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "16"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1210
              #items: array:1 [
                0 => App\Models\Book {#1168}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1255
              #items: array:1 [
                0 => App\Models\Branch {#1209
                  #connection: "mysql"
                  #table: "branches"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:24 [
                    "id" => 1434852
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_display_title" => "Оптика"
                    "field_branch_order" => "8"
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1213
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_page_start" => "15"
                    "field_branch_display" => "0"
                    "field_branch_expanded" => "0"
                    "field_display_branch_in_title" => "1"
                    "field_display_task_interval" => "0"
                    "field_display_branch_page" => "1"
                    "field_branch_title_in_content" => "0"
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            "text" => "<p><strong>2*.</strong> Непрозрачный шар $\text{Ш}$ освещают точечным источником света $\text{S}$, который расположен на прямой, проходящей через центр шара и перпендикулярной плоскости экрана $\text{Э}$ (рис. 15). Постройте изображение тени от непрозрачного шара на экране. Вычислите радиус $\text{R}$ тени, если расстояние между источником и центром шара $L = 1 \text{ м}$, а расстояние от центра шара до экрана $H = 0,5 \text{ м}$. Радиус шара $r = 20 \text{ см}$.</p><p>Рис. 15</p><p><strong>Подсказка.</strong> Используйте теорему Пифагора и признаки подобия треугольников.</p><p><em>Решение.</em></p><p><em>Ответ:</em> ___________.</p>"
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            "text" => "<p><strong>2*.</strong> Непрозрачный шар $\text{Ш}$ освещают точечным источником света $\text{S}$, который расположен на прямой, проходящей через центр шара и перпендикулярной плоскости экрана $\text{Э}$ (рис. 15). Постройте изображение тени от непрозрачного шара на экране. Вычислите радиус $\text{R}$ тени, если расстояние между источником и центром шара $L = 1 \text{ м}$, а расстояние от центра шара до экрана $H = 0,5 \text{ м}$. Радиус шара $r = 20 \text{ см}$.</p><p>Рис. 15</p><p><strong>Подсказка.</strong> Используйте теорему Пифагора и признаки подобия треугольников.</p><p><em>Решение.</em></p><p><em>Ответ:</em> ___________.</p>"
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            "text" => "<p><strong>Построение</strong></p><p>Тень от непрозрачного шара на экране представляет собой круг. Его граница образуется лучами света, которые исходят из точечного источника $S$ и касаются поверхности шара. Эти лучи образуют конус. Тень на экране — это сечение этого конуса плоскостью экрана. Из-за симметрии задачи (источник, центр шара и центр экрана лежат на одной прямой, перпендикулярной экрану) тень будет кругом, центр которого находится в точке пересечения этой прямой с экраном.</p><p><strong>Вычисление</strong></p><p><strong>Дано:</strong></p><p>Расстояние от источника до центра шара $L = 1$ м</p><p>Расстояние от центра шара до экрана $H = 0,5$ м</p><p>Радиус шара $r = 20$ см $= 0,2$ м</p><p><strong>Найти:</strong></p><p>Радиус тени $R$ — ?</p><p><strong>Решение:</strong></p><p>Для нахождения радиуса тени $R$ рассмотрим осевое сечение системы, проходящее через источник света $S$, центр шара $O$ и центр тени на экране $P$. В этом сечении шар выглядит как окружность радиусом $r$, а тень — как отрезок, половина длины которого равна радиусу тени $R$.</p><p>Пусть луч, исходящий из источника $S$, касается шара в точке $A$. Тогда радиус $OA$, проведенный в точку касания, перпендикулярен касательной $SA$. Таким образом, треугольник $\triangle SAO$ является прямоугольным с прямым углом при вершине $A$. Гипотенуза этого треугольника — отрезок $SO$, равный $L$. Катеты — радиус шара $OA = r$ и отрезок касательной $SA$.</p><p>Этот же луч, продолжаясь, пересекает экран в точке $B$, которая лежит на границе тени. Расстояние от центра тени $P$ до точки $B$ равно радиусу тени $R$. Поскольку прямая $SP$ перпендикулярна экрану, треугольник $\triangle SBP$ также является прямоугольным с прямым углом при вершине $P$. Его катеты — $SP$ и $PB=R$. Длина катета $SP$ равна сумме расстояний от источника до центра шара и от центра шара до экрана: $SP = SO + OP = L + H$.</p><p>Треугольники $\triangle SAO$ и $\triangle SBP$ имеют общий острый угол при вершине $S$. Используя определения тригонометрических функций для этого угла в обоих треугольниках, мы можем связать их стороны.</p><p>Из прямоугольного треугольника $\triangle SAO$:</p><p>$\sin(\angle S) = \frac{OA}{SO} = \frac{r}{L}$</p><p>Из прямоугольного треугольника $\triangle SBP$:</p><p>$\tan(\angle S) = \frac{PB}{SP} = \frac{R}{L+H}$</p><p>Используем основное тригонометрическое тождество и связь между синусом и тангенсом: $\tan^2(\angle S) = \frac{\sin^2(\angle S)}{\cos^2(\angle S)} = \frac{\sin^2(\angle S)}{1-\sin^2(\angle S)}$.</p><p>Подставим наши выражения:</p><p>$(\frac{R}{L+H})^2 = \frac{(r/L)^2}{1 - (r/L)^2} = \frac{r^2/L^2}{(L^2-r^2)/L^2} = \frac{r^2}{L^2-r^2}$</p><p>Извлечем квадратный корень из обеих частей уравнения:</p><p>$\frac{R}{L+H} = \frac{r}{\sqrt{L^2-r^2}}$</p><p>Выразим искомый радиус тени $R$:</p><p>$R = \frac{r(L+H)}{\sqrt{L^2-r^2}}$</p><p>Теперь подставим числовые значения из условия задачи:</p><p>$R = \frac{0,2 \cdot (1 + 0,5)}{\sqrt{1^2 - (0,2)^2}} = \frac{0,2 \cdot 1,5}{\sqrt{1 - 0,04}} = \frac{0,3}{\sqrt{0,96}}$ м</p><p>Упростим знаменатель: $\sqrt{0,96} = \sqrt{\frac{96}{100}} = \frac{\sqrt{16 \cdot 6}}{10} = \frac{4\sqrt{6}}{10} = \frac{2\sqrt{6}}{5}$.</p><p>$R = \frac{0,3}{2\sqrt{6}/5} = \frac{0,3 \cdot 5}{2\sqrt{6}} = \frac{1,5}{2\sqrt{6}} = \frac{1,5 \cdot \sqrt{6}}{2 \cdot 6} = \frac{1,5\sqrt{6}}{12} = \frac{\sqrt{6}}{8}$ м.</p><p>Для практического представления вычислим приближенное значение: $R \approx \frac{2,449}{8} \approx 0,306$ м.</p><p><strong>Ответ:</strong> Радиус тени $R = \frac{\sqrt{6}}{8} \text{ м} \approx 30,6 \text{ см}$.</p>"
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            "text" => "<p><strong>Построение</strong></p><p>Тень от непрозрачного шара на экране представляет собой круг. Его граница образуется лучами света, которые исходят из точечного источника $S$ и касаются поверхности шара. Эти лучи образуют конус. Тень на экране — это сечение этого конуса плоскостью экрана. Из-за симметрии задачи (источник, центр шара и центр экрана лежат на одной прямой, перпендикулярной экрану) тень будет кругом, центр которого находится в точке пересечения этой прямой с экраном.</p><p><strong>Вычисление</strong></p><p><strong>Дано:</strong></p><p>Расстояние от источника до центра шара $L = 1$ м</p><p>Расстояние от центра шара до экрана $H = 0,5$ м</p><p>Радиус шара $r = 20$ см $= 0,2$ м</p><p><strong>Найти:</strong></p><p>Радиус тени $R$ — ?</p><p><strong>Решение:</strong></p><p>Для нахождения радиуса тени $R$ рассмотрим осевое сечение системы, проходящее через источник света $S$, центр шара $O$ и центр тени на экране $P$. В этом сечении шар выглядит как окружность радиусом $r$, а тень — как отрезок, половина длины которого равна радиусу тени $R$.</p><p>Пусть луч, исходящий из источника $S$, касается шара в точке $A$. Тогда радиус $OA$, проведенный в точку касания, перпендикулярен касательной $SA$. Таким образом, треугольник $\triangle SAO$ является прямоугольным с прямым углом при вершине $A$. Гипотенуза этого треугольника — отрезок $SO$, равный $L$. Катеты — радиус шара $OA = r$ и отрезок касательной $SA$.</p><p>Этот же луч, продолжаясь, пересекает экран в точке $B$, которая лежит на границе тени. Расстояние от центра тени $P$ до точки $B$ равно радиусу тени $R$. Поскольку прямая $SP$ перпендикулярна экрану, треугольник $\triangle SBP$ также является прямоугольным с прямым углом при вершине $P$. Его катеты — $SP$ и $PB=R$. Длина катета $SP$ равна сумме расстояний от источника до центра шара и от центра шара до экрана: $SP = SO + OP = L + H$.</p><p>Треугольники $\triangle SAO$ и $\triangle SBP$ имеют общий острый угол при вершине $S$. Используя определения тригонометрических функций для этого угла в обоих треугольниках, мы можем связать их стороны.</p><p>Из прямоугольного треугольника $\triangle SAO$:</p><p>$\sin(\angle S) = \frac{OA}{SO} = \frac{r}{L}$</p><p>Из прямоугольного треугольника $\triangle SBP$:</p><p>$\tan(\angle S) = \frac{PB}{SP} = \frac{R}{L+H}$</p><p>Используем основное тригонометрическое тождество и связь между синусом и тангенсом: $\tan^2(\angle S) = \frac{\sin^2(\angle S)}{\cos^2(\angle S)} = \frac{\sin^2(\angle S)}{1-\sin^2(\angle S)}$.</p><p>Подставим наши выражения:</p><p>$(\frac{R}{L+H})^2 = \frac{(r/L)^2}{1 - (r/L)^2} = \frac{r^2/L^2}{(L^2-r^2)/L^2} = \frac{r^2}{L^2-r^2}$</p><p>Извлечем квадратный корень из обеих частей уравнения:</p><p>$\frac{R}{L+H} = \frac{r}{\sqrt{L^2-r^2}}$</p><p>Выразим искомый радиус тени $R$:</p><p>$R = \frac{r(L+H)}{\sqrt{L^2-r^2}}$</p><p>Теперь подставим числовые значения из условия задачи:</p><p>$R = \frac{0,2 \cdot (1 + 0,5)}{\sqrt{1^2 - (0,2)^2}} = \frac{0,2 \cdot 1,5}{\sqrt{1 - 0,04}} = \frac{0,3}{\sqrt{0,96}}$ м</p><p>Упростим знаменатель: $\sqrt{0,96} = \sqrt{\frac{96}{100}} = \frac{\sqrt{16 \cdot 6}}{10} = \frac{4\sqrt{6}}{10} = \frac{2\sqrt{6}}{5}$.</p><p>$R = \frac{0,3}{2\sqrt{6}/5} = \frac{0,3 \cdot 5}{2\sqrt{6}} = \frac{1,5}{2\sqrt{6}} = \frac{1,5 \cdot \sqrt{6}}{2 \cdot 6} = \frac{1,5\sqrt{6}}{12} = \frac{\sqrt{6}}{8}$ м.</p><p>Для практического представления вычислим приближенное значение: $R \approx \frac{2,449}{8} \approx 0,306$ м.</p><p><strong>Ответ:</strong> Радиус тени $R = \frac{\sqrt{6}}{8} \text{ м} \approx 30,6 \text{ см}$.</p>"
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№2 (с. 17)
Условие. №2 (с. 17)
скриншот условия
Физика, 9 класс рабочая тетрадь, авторы: Грачев Александр Васильевич, Погожев Владимир Александрович, Боков Павел Юрьевич, Вишнякова Екатерина Анатольевна, издательство Просвещение, Москва, 2021, Часть 3, страница 17, номер 2, Условие
Физика, 9 класс рабочая тетрадь, авторы: Грачев Александр Васильевич, Погожев Владимир Александрович, Боков Павел Юрьевич, Вишнякова Екатерина Анатольевна, издательство Просвещение, Москва, 2021, Часть 3, страница 17, номер 2, Условие (продолжение 2)

2*. Непрозрачный шар $\text{Ш}$ освещают точечным источником света $\text{S}$, который расположен на прямой, проходящей через центр шара и перпендикулярной плоскости экрана $\text{Э}$ (рис. 15). Постройте изображение тени от непрозрачного шара на экране. Вычислите радиус $\text{R}$ тени, если расстояние между источником и центром шара $L = 1 \text{ м}$, а расстояние от центра шара до экрана $H = 0,5 \text{ м}$. Радиус шара $r = 20 \text{ см}$.

Рис. 15

Подсказка. Используйте теорему Пифагора и признаки подобия треугольников.

Решение.

Ответ: ___________.

Решение. №2 (с. 17)

Построение

Тень от непрозрачного шара на экране представляет собой круг. Его граница образуется лучами света, которые исходят из точечного источника $S$ и касаются поверхности шара. Эти лучи образуют конус. Тень на экране — это сечение этого конуса плоскостью экрана. Из-за симметрии задачи (источник, центр шара и центр экрана лежат на одной прямой, перпендикулярной экрану) тень будет кругом, центр которого находится в точке пересечения этой прямой с экраном.

Вычисление

Дано:

Расстояние от источника до центра шара $L = 1$ м

Расстояние от центра шара до экрана $H = 0,5$ м

Радиус шара $r = 20$ см $= 0,2$ м

Найти:

Радиус тени $R$ — ?

Решение:

Для нахождения радиуса тени $R$ рассмотрим осевое сечение системы, проходящее через источник света $S$, центр шара $O$ и центр тени на экране $P$. В этом сечении шар выглядит как окружность радиусом $r$, а тень — как отрезок, половина длины которого равна радиусу тени $R$.

Пусть луч, исходящий из источника $S$, касается шара в точке $A$. Тогда радиус $OA$, проведенный в точку касания, перпендикулярен касательной $SA$. Таким образом, треугольник $\triangle SAO$ является прямоугольным с прямым углом при вершине $A$. Гипотенуза этого треугольника — отрезок $SO$, равный $L$. Катеты — радиус шара $OA = r$ и отрезок касательной $SA$.

Этот же луч, продолжаясь, пересекает экран в точке $B$, которая лежит на границе тени. Расстояние от центра тени $P$ до точки $B$ равно радиусу тени $R$. Поскольку прямая $SP$ перпендикулярна экрану, треугольник $\triangle SBP$ также является прямоугольным с прямым углом при вершине $P$. Его катеты — $SP$ и $PB=R$. Длина катета $SP$ равна сумме расстояний от источника до центра шара и от центра шара до экрана: $SP = SO + OP = L + H$.

Треугольники $\triangle SAO$ и $\triangle SBP$ имеют общий острый угол при вершине $S$. Используя определения тригонометрических функций для этого угла в обоих треугольниках, мы можем связать их стороны.

Из прямоугольного треугольника $\triangle SAO$:

$\sin(\angle S) = \frac{OA}{SO} = \frac{r}{L}$

Из прямоугольного треугольника $\triangle SBP$:

$\tan(\angle S) = \frac{PB}{SP} = \frac{R}{L+H}$

Используем основное тригонометрическое тождество и связь между синусом и тангенсом: $\tan^2(\angle S) = \frac{\sin^2(\angle S)}{\cos^2(\angle S)} = \frac{\sin^2(\angle S)}{1-\sin^2(\angle S)}$.

Подставим наши выражения:

$(\frac{R}{L+H})^2 = \frac{(r/L)^2}{1 - (r/L)^2} = \frac{r^2/L^2}{(L^2-r^2)/L^2} = \frac{r^2}{L^2-r^2}$

Извлечем квадратный корень из обеих частей уравнения:

$\frac{R}{L+H} = \frac{r}{\sqrt{L^2-r^2}}$

Выразим искомый радиус тени $R$:

$R = \frac{r(L+H)}{\sqrt{L^2-r^2}}$

Теперь подставим числовые значения из условия задачи:

$R = \frac{0,2 \cdot (1 + 0,5)}{\sqrt{1^2 - (0,2)^2}} = \frac{0,2 \cdot 1,5}{\sqrt{1 - 0,04}} = \frac{0,3}{\sqrt{0,96}}$ м

Упростим знаменатель: $\sqrt{0,96} = \sqrt{\frac{96}{100}} = \frac{\sqrt{16 \cdot 6}}{10} = \frac{4\sqrt{6}}{10} = \frac{2\sqrt{6}}{5}$.

$R = \frac{0,3}{2\sqrt{6}/5} = \frac{0,3 \cdot 5}{2\sqrt{6}} = \frac{1,5}{2\sqrt{6}} = \frac{1,5 \cdot \sqrt{6}}{2 \cdot 6} = \frac{1,5\sqrt{6}}{12} = \frac{\sqrt{6}}{8}$ м.

Для практического представления вычислим приближенное значение: $R \approx \frac{2,449}{8} \approx 0,306$ м.

Ответ: Радиус тени $R = \frac{\sqrt{6}}{8} \text{ м} \approx 30,6 \text{ см}$.

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