Cho ΔABC vuông tại A, đường cao AH. Chứng minh ΔHBA ~ ΔHCA. Lưu ý: Ko sử dụng tính chất bắc cầu. Sử dụng tính chất hai góc bằng nhau vì cùng phụ một góc để chứng minh Mn ơi, help me PLEASE Bạn gì đó ơi trả lời thì trả lời nhanh giùm mình dc ko, mình đang bận

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II. Complete the sentences, putting the verbs into the correct tenses: 1. I (get) _______ hungry. Let’s go and have something to eat 2. Be quiet! I (want) _______ to hear the news broadcast 3. What _______ you (do) yesterday? I (get) _______ up very early, (have) _______ my breakfast and then I (go) _______ to my office 4. Egypt (produce) _______ some of the finest cotton in the world 5. What _______ she (do) when you (arrive) _______ at her house yesterday morning? She (cook) _______ her breakfast in the kitchen 6. What _______ you usually (read) when you (be) _______ on holiday? I (read) _______ detective stories. Now I (read) _______ “The Shut door” by Ivor Lock 7. Ann (wait) _______ for me when I (arrive) _______ 8. Mary (usually/phone) _______ me on Fridays but She (not phone) _______ last Friday 9. What’s the noise? What (happen) _______ ? 10. Yesterday evening, the phone (ring) _______ three times while we (have) _______ dinner 11. Why are you under the table? You (look) _______ for something? 12. _______ You (watch) TV last night? No, I (have) _______ supper and (go) _______ straight to bed 13. I (not like) _______ staying at hotels, but last summer, we (spend) _______ a few days at a very nice hotel by the sea. 14. Linda (be) _______ busy when we (go) _______ to see her yesterday. She (study) _______ for an exam. We (not want) _______ to disturb her, so we (not stay) _______ very long 15. When I first (tell) _______ Tom the news, he (not believe) _______ me. He (think) _______ that I (joke) _______ 16. We usually (go) _______ to Spain on holiday, but this year we (go) _______ to France 17. We can go out now. It (not rain) _______ any more 18. The sun (warm) _______ the air and (give) _______ us light 19. What speed _______ the car (do) at the time of the accident? 20. They (study) _______ in the library when the fire alarm (go) _______ off