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 Наступление общецивилизационного кризиса. Причины и характер первой мировой войны

В треугольнике АВС угол А = 75 градусов , угол В = 30 градусов , АВ = 10 см . Найдите площадь треугольника. СПС !!! 

. Поставьте глагол в скобках в требуемом по смыслу вре¬мени: 1. I not (to see) your brother lately. 2. You ever (to see) the sea? 3. When I (to come in) he just (to finish) his homework. 4. He suddenly (to realize) that he (to leave) his umbrella in the bus. 5. He (to bathe) in the river when it (to begin) to rain. 6. The train (to arrive) 10 minutes ago. 7. It's time to wake him up. He (to sleep) for ten hours. 8. He often (to go) to the skating-rink last winter. 9. He (to cross) the street when I (to call) him. 10. What (to happen) to you? You are so excited! 11. I can't tell you her telephone number, as I (to forget) it. 12. Where you (to put) my hat? I can't find it. 13. When he (to come) into the room, he saw a man who (to sit) on the sofa. He at once (to remember) that it was the man he (to see) at his brother's a few days before. 14. When I (to call) at his house they (to tell) me that he (to leave) an hour before. 15. Where is P.? He (to go) home. He (to leave) the room a few min¬utes ago. 16. Let's have dinner, Peter. -No, thank you. I already (to have) din¬ner. 17. He (to return) home very late, as he (to lose) his way in the fog. 18. We (to know) each other since I (to come) to Moscow. 19. The ship (to cover) already half the distance when a storm (to break out). 20. When we were in the Crimea we (to visit) the places where we (to live) in our childhood. 21. You (to read) "great Expectations" by Dickens? - Yes, I (to read) it many years ago. 22. He (to be) a party member since 1945. 23. It is time to begin the meeting, as all the students (to come).

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