Một đầu máy kéo một đoàn tàu với lực 20000 N đi được quãng đường 15 km trong 10 min. a) Tính công suất đoàn tàu. b) Tính tốc độ của đoàn tàu.

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V. Supply the correct form of the words in brackets. 1. Rossie has a large ______________ (collect)of dolls. 2. A______________ is someone who enjoys watching birds. (birdwatch) 3. My sister’s hobby is ______________.She took a lot of nice photos. (photo) 4. I find woodcarving ______________ because it’s a creative activity. (interest) 5. ______________ eggshells are unique gifts for family and friends. (carve) 6. A hobby is an ______________ that you do for pleasure. (act) 7. I think collecting glass bottles is ______________. (usual) 8. Susan is very ______________ and she paints very well. (create) VI. There is one mistake in each sentence. Underline and correct the mistake. 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? VII. Match the questions with the answer. 1. Will you go swimming tomorrow? 2. Does your mother like watching films on TV? 3. What do you think about windsurfing? 4. Will you take up carving eggshells someday? 5. Why do you find making models boring? 6. What are your hobbies? 7. When did your brother start painting? 8. Does she have any difficult hobby? a. I think it is dangerous. b. Nope, I have another plan. c. Maybe. I find it really interesting. d. Yes, she enjoys mountain biking. e. No, she loves going to the cinema. f. About three years ago. g. Because it takes too much time. h. Swimming and playing chess.