Cho hình bình hành ABCD . Gọi H và K lần lượt là hình chiếu của A và C trên đường chéo BD a) Chứng minh : AHCK là hình bình hành b) Gọi O là trung điểm của HK. Chứng minh: A đối xứng với C qua O

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MN GIẢI THK CHI TIẾT GIÚP MK VS III. Choose best answer A, B, or C to complete the sentences. 11. Today’s cities are ______ than cities in previous time. A. lots larger B. much larger C. as large D. the largest 12. This laptop is much more user-friendly, but it costs_____ the other one. A. so much as B. as many as C. twice as much as D. twice as many 13. We expected her at nine but she finally _______ at eleven. A. turned upB. turned out C. came over D. grew up 14. Ann is taking extra lessons to _______ what she missed while she was sick. A. take back B. get on well withC. keep up with D. look forward to 15. You should take your shoes _______when you go into the temples. A. up B. in C. off D. on 16. It is considered that life in a city is wonderful and _______. A. funny B. boring C. enjoyable D. helpful 17. Let me know when you come to Ha Noi and I’ll _______. A. take you out B. bring you around C. cheer you up D. show you around 18. The city has recently set _____ a library in the West Suburb. A. up B. off C. out D. down 19. I don’t think Fred gets _____ well with Daniel. They always argue. A. over B. through C. on D.in 20. You should take your hat _____ in the cinema. A. in B. over C. off D. down 21. We were shown _____ the town by a volunteer student. A. up B. off C. around D. on 22. After I found all the information I needed, I_______ the computer. A. turned off B. switched on C. looked for D. put off 23. She turned _______ the new job in New York because she didn’t want to move. A. on B. down C .of D. up 24. On children festival, the zoo is always _______ with people, mainly children. A. packed B. had C. contained D. scored 25. Remember to _______ your shoes when you are in a Japanese house. A. put off B. turn off C. take off D. give up