3. (Have you packed / Did you pack) everything? What time (will you / are you going to / do you) start tomorrow? - We ... (shall start / are going to start / start) at 7 o'clock.

Решение:

Для вопроса о действиях, запланированных на конкретное время в будущем, используется Present Simple (для расписаний) или Future Simple ('will') / 'be going to' для общих планов. В данном случае, речь идет о планах на завтра.

1. Did you pack everything? What time are you going to start tomorrow? - We are going to start at 7 o'clock.

Ответ: Did you pack, are you going to, are going to start