Какую формулу используют для описания срока службы изоляционной конструкции как случайной величины?<img src="/close/store/examRes/%7B3B131D59-724F-4D7C-ADD9-85F882C75C72%7D/%D0%B8%D1%82%D0%BE%D0%B3%28%D0%AD%D0%92%D0%9E%29_%D0%B2%D0%BE%D0%BF%D1%80%D0%BE%D1%81_7%282%29.png" /><img src="/close/store/examRes/%7B3B131D59-724F-4D7C-ADD9-85F882C75C72%7D/%D0%B8%D1%82%D0%BE%D0%B3%28%D0%AD%D0%92%D0%9E%29_%D0%B2%D0%BE%D0%BF%D1%80%D0%BE%D1%81_7%281%29.png" /><img src="/close/store/examRes/%7B3B131D59-724F-4D7C-ADD9-85F882C75C72%7D/%D0%B8%D1%82%D0%BE%D0%B3%28%D0%AD%D0%92%D0%9E%29_%D0%B2%D0%BE%D0%BF%D1%80%D0%BE%D1%81_7%283%29.png" /><img src="/close/store/examRes/%7B3B131D59-724F-4D7C-ADD9-85F882C75C72%7D/%D0%B8%D1%82%D0%BE%D0%B3%28%D0%AD%D0%92%D0%9E%29_%D0%B2%D0%BE%D0%BF%D1%80%D0%BE%D1%81_7%284%29.png" /> <img src="/close/store/examRes/%7B3B131D59-724F-4D7C-ADD9-85F882C75C72%7D/%D0%B8%D1%82%D0%BE%D0%B3%28%D0%AD%D0%92%D0%9E%29_%D0%B2%D0%BE%D0%BF%D1%80%D0%BE%D1%81_7%281%29.png" />, <img src="/close/store/examRes/%7B3B131D59-724F-4D7C-ADD9-85F882C75C72%7D/%D0%B8%D1%82%D0%BE%D0%B3%28%D0%AD%D0%92%D0%9E%29_%D0%B2%D0%BE%D0%BF%D1%80%D0%BE%D1%81_7%282%29.png" />, <img src="/close/store/examRes/%7B3B131D59-724F-4D7C-ADD9-85F882C75C72%7D/%D0%B8%D1%82%D0%BE%D0%B3%28%D0%AD%D0%92%D0%9E%29_%D0%B2%D0%BE%D0%BF%D1%80%D0%BE%D1%81_7%283%29.png" />, <img src="/close/store/examRes/%7B3B131D59-724F-4D7C-ADD9-85F882C75C72%7D/%D0%B8%D1%82%D0%BE%D0%B3%28%D0%AD%D0%92%D0%9E%29_%D0%B2%D0%BE%D0%BF%D1%80%D0%BE%D1%81