помогите пожалуйсто 2 : 1/4 +((1 1/2 + 2  2/3 ) :3 3/4 - 2/3) 8 8/9 

Open the brackets.

6. Della (to hurry)__________ from shop to shop looking for a present for Jim.7. The other day my sister and I (to go)_____________ shopping together. We (to enter)____________ a big shop in Arbat street. While my sister (to choose)____________ a new hat, I (to look for)____________ a pair of gloves.8. The moment he (to hear)_________ the news, Jim (to call)___________ me by telephone.9. Just as I (to leave)_________ for home, a student (to stop)_________ me in the hall. 10. When I last (to see)_________ her she (to hurry)__________ along the road to the station. I (to ask)__________ her where she (to go)_______ and she (to say)________ London, but I don’t think she (to tell)________ the truth because there (not to be)_________ any train to London at that time.

Напишите уравнения реакций, с помощью которых можно осуществим, цепочки превращений веществ:

1) Сера →Сероводород →Сера → Сульфид меди(П) → Сернистый газ;

2) Сера →Сульфид железа(И) → Сероводород → Гидросульфид натрия →Сульфид натрия → Сера;