Cho △ ABC có góc A=90 . Lấy điểm H trên cạnh AC.E là hính chiếu của H lên BC a)Chứng minh:ΔABC đồng dạng ΔEHC b)chứng minh:góc HBC=EAC c)Gọi I là giao điểm của đoạn AE và BH C/m:AB.HI=AI.HE Giúp vs đang cần cực gấp nhất là câu c

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SECTION 2: PHONETICS.III III. Choose the word whose underlined part is pronounced differently from the rest by circling the corresponding letter A, B, C or D. (1,2 point) 1. A. plays B. says C. days D. stays 2. A. what B. who C. where D. when 3. A. sport B. start C. listen D. eat 4. A. game B. geography C. vegetable D. change 5. A. station B. intersection C. question D. invitation 6. A. teacher B. children C. lunch D. chemistry IV. Choose the word with different stress pattern. Write A, B, C or D in the space provided(0.8pt) 7. A. delicious B. difficult C. dangerous D. different 8. A. activity B. badminton C. basketball D. aerobics 9 A. sandwich B. chocolate C. cartoon D. toothpaste 10. A. correct B. receive C. visit D. unload SECTION 3: VOCABULARY & GRAMMAR.V. Choose the best answer to complete each sentence, identify your answer by circling the corresponding letter A, B, C, or D. )(4.0 points) 1. You can watch Harry Potter on TV ________ you can read it. A. so B. and C. but D. or 2. “- ________ a nice T-shirt, Trang!” _ “ Thank you” A. How B.What C. Which D. It 3. “- ________ films have you seen this week ?” _ “ Only one” A. How many B. What C. Which D. Who 4. There aren’t ________ good films on TV at the moment A. some B. any C. much D. a lot 5. If we cut down more trees, there ________ more floods. A. are B. were C. have been D. will be 6. That is ________ book I’ve ever read . A. the borest B. the boring C. the most boring D. the most bored 7. The opposite of "polluted " is .................... A. fresh B. good C. dirty D. safe 8.We should use reusable water bottles ___________ of plastic ones. A. instead B. because C. despite D. however 9. In the future, we won’t go on holiday to the beach but we ________ go on holiday to the moon. A. must B. can’t C. might D. won’t 10. ________ you swim when you were ten? A. Can B. Could C. Will D. Might 11. My father likes watching TV____________ he doesn’t like listening to music. A. and B. so C. but D. because 12. We should use _____________pens and pencils to reduce rubbish. A. reliable B.reusable C. refillable D. sociable 13. In the future, we will have ___________to do housework. A. robots B. wireless TV C. smart phone D. hi-tech fridge 14. Eiffel Tower is the most attractive ____________in France. A. building B. resort C. square D. landmark 15. We should use _________to save natural resources. A. oil B. solar energy C. coal D. gas 16._______________ means creating new products from used materials. A. Reduce B. Reuse C. Recycle D. Rebuild 17. If the ______________ is polluted, we won’t have enough food to eat. A. water B. air C. noise D. soil 18.We should give unused clothes to_____________to help the people in need... A. charity B. factory C. market D. hospital 19. ___________ are you going to stay here? ~ For a week. A. How often B. How long C. How many D. How far 20. ______________.happens when water in lakes,rivers and oceans is polluted. A. Air pollution B. Soil pollution C. Water pollution D. Noise pollution VI. Supply the correct tense or form of the verbs in brackets. (2.0 points) 1. How long have you ( wait )_______ been waiting for me? – Just a few minutes. 2. Tony can (speak)________ speak two languages. 3. Every evening, my father (watch)______ watches television. 4. His parents (buy) are buying a new house next month? 5. Le Tam wants to be (be)________ a teacher after he leaves school .6. There are lots of gray clouds in the sky. It (rain)_______ is raining. 7. Where is your mom now? - She (grow)_______ is growing vegetables in the garden. 8. children like ( ride)______ e-bikes to school 9. how much fruit thát farmer (produce)_______ every year? 10. he often says OK when he ( talk) ____________ with the guests.