В 3 одинаковых стаканах 600 г воды. Можно ли сказать, что в 5 таких стаканах будет 1 кг воды?

1. I have just had breakfast.
2. He has already had breakfast.
3. We hasn't yet had breakfast.
4. They are still drinking tea in the dining-room.
5. I have already had the lessons.
6. He is still doing his lessons.
7. We had three lessons today.
8. They have just had meeting.
9. She hasn't read this book yet.
10. She is still reading.