1)Прямоугольник  с боковой стороной 4 см и основание 5 см является осевым сечением цилиндра. Найти его обьем?
2)В равностороннем конусе радиус основания равен 2 см. Найти площадь сечения проведенного через 2 образующие, угол между котороми равен 30 Градусам

Окно состоит из квадрата и полуокружности .Сторона квадрата равна 2 м.
Периметр окна равен?

Переделайте следующие предложения в Active Voice. Введите любые подходящие подлежащие.

1. The room was cleaned and aired. 2. Have all these books been read? 3. Whom were these letters written by? 4. The letter has just been typed. 5. She showed me the picture which had been painted by her husband. 6. I shall not be allowed to go there. 7. He has been told everything, so he knows what to do now. 8. All the questions must he answered. 9. The door has been left open. 10. Betty was rnet at the station. 11. The girl was not allowed to go to the concert. 12. She said that the new timetable had not yet been hung up on the notice board. 13. The roast chicken was eaten with appetite. 14. It was so dark, that the houses could not be seen. 15. The light has not yet been turned off. 16. The boy was punished for misbehaving. 17. By three o'clock everything had been prepared. 18. The dictation was written without mistakes. 19. Whom was the poem written by? 20. Her dress was washed and ironed. 21. I was not blamed for the mistakes. 22. The papers had been looked through and corrected by the next lesson. 23. This house was built last year. 24. The letter has just been sent. 25. This article will be translated at the lesson on Tuesday. 26. When will this book be returned to the library?

в колебательный контур включен конденсатор емкостью 200 пФ. Какую индуктивность нужно включить в контур, чтобы в нем электрические колебания с частотой 400 кГц