Giúp mình câu này với! Một xe có khối lượng $1,5$ $tấn$ bắt đầu chuyển động. Sau $\dfrac{1}{3}$ phút xe đi được $100m$. Biết hệ số ma sát $k=0,25$ , $g=10m/s^2$ a) Tính lực kéo tác dụng lên xe. b) Sau khi đạt vận tốc $54km/h$ thì triệt tiêu lực. Tìm quãng đường xe đi được kể từ khi triệt tiêu lực kéo.

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.❷. MULTIPLE CHOICE I. Choose the best answer to complete each of the following sentences. I. Choose the best answer to complete each of the following sentences. 1. Nowadays people hours sitting in front of computers. A. spend B. last C. set D. take 2. I think you should take up swimming _____it is suitable for your health condition. A. so B. because C. although D. but 3. My family enjoys because we can sell vegetables and flowers money. A. garden - to B. gardening - for C. gardening - with D. garden - of 4. If your hobby is greeting card making, you can give your to your friends as presents. A. hobby B. money C. greetings D. products 5. My sister’s hobby is sewing, and she can get the sewing patterns from the ___ magazines. A. fashion B. cooking C. sports D. science 6. My brother doesn’t like ice-skating because he thinks it is . A. danger B. in danger C. dangerous D. endangered 7. My sister is very keen on swimming, and she goes swimming three __ a week. A. time B. a time C. times D. timings 8. We often read the instructions carefully in order to make of the things we like best. A. meanings B. models C. copies D. uses 9. You need to be to follow eggshell carving because it may take two weeks to complete one shell. A. careful B. interesting C. fit D. patient 10. If you choose sewing as your hobby, you will your own clothes. A. do B. make C. take D. get 11. There are many why it is important to have a hobby. A. answers B. reasons C. details D. facts 12. Will you making models in the future? A. pick up B. look for C. take up D. find 13. Do you think that hobby is and boring? A. easy B. difficult C. danger D. interesting 14. I love my sister’s paintings because she is very in using colors. A. careless B. care C. creative D. imagine 15. A hobby helps you to connect with people. A. other B. others C. another D. the other 16. I join a photography club, and all members love photos. A. take B. taking C. make D. making 17. What does your father do his free time? A. in B. at C. on D. while 18. I think a hobby will always give you and help you . A. pleased - relax B. pleasure - relaxed C. pleased - relaxing D. pleasure - relax 19. You can share your stamps other collectors a stamp club. A. with - at B. to - at C. with - in D. to - in 20. I think this hobby does not cost you much, and you need is time. A. most B. all of C. some D. all 21. Hoa likes music. She often …………. to music in late evenings. A. listen B. listening C. listens D. to listens 22. I enjoy …………. baminton after school. A. doing B. playing C. seeing D. going 23. Ann has a large …………. of stamps. A. collect B. collection C. collecting D. collections 24. How ………….do you go to the library after school? A. often B. much C. many D. usually 25. My sister usually goes to the library with me. She likes___ comic books very much. A. read B. reading C. to read D. reads 26. In big cities, there are many kinds of _____ for young people. A. entertain B. entertains C. entertainment D. entertaining 27. What _____ does Minh like playing in his free time? A. activities B. sports C. things D. subjects 28. He goes swimming when he ______ free time. A. have B. is having C. has D. will have 29. My uncle likes ______ the vegetables we grow ourselves. A. to eat B. eat C. eats D. eating 30. My close friend draws very well. She will be a …………. artist one day. A. fame B. famous C. famously D. famed

❺. CORRECTION I. Choose the underlined word or phrase (marked A, B, C or D) in each sentence that needs correcting. 1. The children are playing boarding games, and their mother is arranging flowers. A B C D 2. One of his father's favourite hobbies is playing horse-riding, and he just practises it A B C twice a month. D 3. He started learning how to play the guitar on his elder brother. A B C D 4.Your favourite football match will begin at 3 p.m., so you should arrive there A B C soon to get a good seat. D 5. She will attend the judo class next month because she intends to have a long A B C vacation in Ho Chi Minh City. D 6. He loves to listen to classical music, but he spends a little time doing it. A B C D 7. She didn't enjoy the party very much because she didn't like music and A B C to dance there. D 8. She’s 18 and she’s France. She lives in a village near Toulouse. She studies A B C engineering at university. D 9. She has a short black hair and very dark eyes. She is intelligent and funny, but A B C sometimes she’s a bit sad too. D 10. She loves music and she likes writing songs. She can plays the guitar very well and A B C she has a beautiful voice. D II. There is one mistake in each sentence. Underline and correct the mistake. Sentences Correction 1. Nam is my classmates. He watches TV every night. 2. I think collecting stamps are interesting. 3. My dad cooks very good. He loves preparing meals for our family. 4. I enjoy to ride my bike to school. 5. We usually go in a small lake out of the city at weekends. 6. Do you still play football next year? 7. We like doing fishing because it is relaxing. 8. Do you think bird-watching interesting? 9. I think playing volleyball interest because it is a team game 10. In my opinion, more people played monopoly in the future.