Question

Массовая доля азота в оксиде составляет 36,8%. Выберите формулу оксида

Answer 1

36,8/14=2,63

63,2/16=3,95

3,95/2,63=1,5

N/0=1n/1.5n

при n=2 фрмула оксида азота N2O3

Answer 2

1. has finished (Present Perfect); may take (Present Simple)
2. was attended (Past Simple)
3. is looked (Present Simple Passive)
4. was told (Past Simple Passive)
5. will be paid (Future Simple Passive)
6. had returned (Past Perfect)
7. will be dressed (Future Simple)
8. is locked (Present Simple Passive)
9. was published (Past Simple Passive)