Cho hình bình hành ABCD , AC cắtt BD tại O. Gọi M , N là trung điểm OD, OB . AM cắt DC tạii E, CN cắt AB tại F a) Chứng minh : AMCN là hình bình hành b) Chứng minh OE=OF c) Chứng minh : DE = 1/2 . EC d) Chứng minh : AC , BD , EF đồng qui

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Question 2:Choose the best answer a, b, c, or d to complete the sentence. (2.0 pts) 5. She is having ______. She's hot and coughs a lot. A. spots B. flu C. earache D. stomachache 6. Although he practised a lot, his legs still ______ weak. A. are B. was C. felt D. has 7. They could not afford to buy the house because it was _______. A. too pretty B. too tight C. too expensive D. too cheap 8. _______ do you do volunteer work? - Every weekend. A. How long B. How far C. How much D. How often 9. Have you ever _______ part in volunteer work? A. taken B. to take C. taking D. take 10.We have raised money for people in need _______ 2015. A. in B.at C. since D. for 11. She’s got a high _______ – almost 40°. A. flu B. headache C. sore throat D. temperature 12. Jane is _______ weight because she eats too much junk food. A. getting over B. putting on C. taking up D. throwing away 13.The charity _______ facilities for disabled people to take part in sport. A. provides B. donates C. raises D. collects 14.I can’t fasten my jeans – I’ll have to _______. A. eat more junk food B. go out regularly C. see my doctor D. go on a diet 15. My favorite hobby is __. I spend most of my free time making vases and bowls from clay. A. carving wood B. making pottery C. making model D. bird watching 16. I’ve already done my homework , _______ I am going to watch TV. A. so B. because C. but D. and 17. They could not afford to buy the house because it was _______. A. too pretty B. too tight C. too expensive D. too cheap 18. _______ do you do volunteer work? - Every weekend. A. How long B. How far C. How much D. How often