một con chim đang bay trên không trung với tốc độ 10m/s, tính vận tốc để sau 5' con chim có mặt trên mặt đất, biết khoảng cách từ đất đến chỗ con chim theo đường chim bay là 8m

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I. Pronunciation: Choose the word whose stress is put differently from the other in group: 1. A. animal B. conservation C. plenty D. various 2. A. submarine B. create C. destruction D. sub-tropical Choose the word whose underlined part is pronounced differently from the other: 3. A. played B. closed C. studied D. laughed ( gạch chân ed) 4. A. pat B. man C. cat D. plant (gạch chân a) II. Vocabulary & Grammar: Choose the best answers to complete the following sentences: 5. Bach Thao zoo ___ many kinds of wild animals, such as lion, tiger. A. covers B. contains C. includes D. consists 6. She ____ to take part in the excursion. A. don’t invite B. haven’t invited C. was not invited D. have been invited 7. QuangOai School was ___ in 1961. A. began B. prepared C. appeared D. established 8. If it ___ fine tomorrow, we’ll go to visit Ba Vi national park. A. is B. was C. would be D. should be 9. What ___ happen if there were no plants on the Earth? A. will B. shall C. would D. does 10. Three-quarters of the earth is covered by ___. A. seas and oceans B. mountains C. soil D. sand 11. We should do something to ___ endangered animals. A. protect B. harm C. purchase D. exchange 12. Vietnam lies in the ___ climate. A. arctic B. pacific C. tropical D. temperate 13. Water ___ held on land by vegetation. A. can be B. were C. are D. was 14. ___ is the most effective way to protect the environment. A. Conservation B. Conservatory C. Conservationist D. Conservatism 15. Today’s scientists send submarines to ___ the undersea world. A. investigating B. investigated C. investigate D. investigation 16. ___ means the existence of different kinds of animals. A. Environment B. Habitat C. Biodiversity D. Marine life 17. Huong pagoda is ___ 50 km from Hanoi. A. situated B. located C. A and B D. bordered 18. Every year, thousands of animals and plants are being ___. A. eliminated B. cut down C. prohibited D. bought 19. __________is a state of being polluted. A. Environment B. Contamination C. Conservation D. conversation 20. The wildlife of animals and plants ________seriously. A. is being threatened B. are being threatened C. is being threatening D. are threatening