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huac2017
2 năm trước
Cho tam giác ABC có góc A =90 độ và AB = AC. a) CM tam giác ẠKB =tam giác AKC và AK vuông góc BC b) Từ C kẻ đường thẳng vuông góc BC và cắt AB tại E. CM EC song song AK c) tính góc BEC
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bạn nào học tốt giúp mình với, vì đây là bài kiểm tra 15 phút nên cần bạn nào làm giúp nghiêm túc nhé I. Choose the word or phrase that best completes each unfinished sentence below. 1. The facsimile _________by Alexander Bain in 1843. A. is invented B. was invented C. invented D. has been invented 2. First, fry the onions ____________add the potatoes. A. than B. then C. after D. before 3. He _______ La prize in the competition last week. A. win B. won C. was won D. has win 4. Who________ the company? A. goes B. walks C. jogs D. runs 5. _______________ is an instrument for making sounds louder. A. Loudspeaker B. Recorder C. Facsimile D. Radio 6. The doctor told me________more fresh fruit. A. eat B. to eat C. eating D. ate 7. Can you______ my bike? A. adjust B. use C. fix D. A&B 8. Coffee was known in Europe “Arabian wine" A. as B. like C. the same D. unlike 9. The information ____________for future use. A. stores B. stored C. is stored D. are stored 10. I saw a ________flying overhead. A. train B. helicopter C. conveyor belt D. coach 11. This beautiful picture ___________ by Mary. A. is drawn B. is drew C. is draw D. is drawing 12. A forest fire ____________ valuable wood, wildlife and good soil. A. is destroyed B. being destroyed C. destroying D. destroys 13. Because of the drought, many people starved to.... A. death B. dead C. deadly D. die 14. The hurricane was ____________, it knocked down all the houses on its way. A. destructive B. destroy C. destruction D. destroying 15. During a long drought, farmers had ____________to find ways to their crops. A. save B. cook C. raise D. set 16. We have to suffer ____________ a lot of floods due to our serious destruction of forests. A. on B. with C. from D. to 17. A heavy storm swept through the village and many people ____________. A. kill B. are killed C. were killed D. killed 18. There was____________ rain yesterday that several roads were flooded. A. too much B. so much C. too many D. so many 19. The heavy rain ____________ floods in the houses by the river. A. caused B. made C. did D. resulted 20. Areas of Africa were ____________ by drought. A. done B. affected C. suffered D. caused

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