Какую функцию выполняет губчатая ткань?

1. Choose the correct verb form (не нужно переписывать, только ответы и объясните мне, почему нужно выбрать так.)

First, she was buying / bought tickets and then she was phoning / phoned John.

While he was reading / read a fil review, his friends were discussing / discussed a film.

On the way home the boys descussed / were discussing the film they had seen.

When did you buy / were you buying this DVD?

The day was wonderful. The birds sang / were singing and the mood was great.

What did you do / were you doing at 9 yesterday?

When he came / was coming to the cinema the film was over.

Brian and Jill were finding / found their seats just as the light went / was going down for the start of the film

They released / were releasing that film in 1999 

К некоторому числу приписали справа нуль.Число увеличилось на 405.Найдите исходное число.С помощью уравнения))))Спасибо за ранее

( 0,8-0,9-0,225) х (дробь восьмь тринадцатых

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0,4:8

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