происхождение восточных словян

Упр. 211. Раскройте скобки, употребляя глаголы в Present Perfect, Present Simple, Present Continuous, Past Simple или Past Continuous.

1. They (to go) to the Hermitage last week. 2. They (to be) to the Hermitage twice this week. 3. After school yesterday he (to come) home, (to have) dinner, (to read) an article from the latest magazine and (to begin) doing his homework. 4. When your friend (to return) from the south? — She (to return) yesterday. — You (to go) to the station to meet her? — No, I..., I (to be) too busy. 5. With whom you (to discuss) this question yesterday? 6. I (to see) this film this week. I like it very much. 7. When I (to enter) the kitchen, I (to see) that my mother (to stand) at the table and (to cut) some cabbage. She (to cook) dinner. 8. As soon as I (to hear) a cry, I (to run) out of the room and (to see) that a child (to lie) on the ground and (to cry). "What (to happen)? Why you (to cry)?

Пожалуйста решите задачу. В прямоугольнике ABCD сторона CD=18 см, диагональ AC образует со стороной CD угол 30 градусов. Найти расстояние от вершины В до диагонали AC.

Осуществите цепочку превращения медь-оксид азота(IV)-азотная кислота-нитрат алюминия-оксид алюминия-сульфат алюминия.

выразите в квадратных метрах:12а 57кв.метров