Một vật chuyển động trên đường thẳng theo phương trình: x = -12 + 2t (m; s). Vận tốc trung bình của vật từ thời điểm t1 = 0,75 s đến t2 = 3 s là: Mọi người giải giúp em với. EM CẢM ƠN.

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Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the following questions My uncle is a well-known writer. He has written a lot of stories for young children. He likes talking and playing with children and he also likes fishing very much. He is very good at fishing. He usually goes to the river behind his house to fish. He often catches a lot of fish but he only keeps the big ones and releases the small ones. He says that fishing gives him the inspiration to write. One summer, he decided to go to the seaside and stayed in a cheap hotel. He went to the sea to fish. He was very glad to catch a lot of big fish on the first day, the second day and so on. He gave all the fish to the kitchen of the hotel and the chef cooked the fish for the guests there. The guests were very happy to eat the fresh fish every day. After a month of staying in the hotel, he decided to come back home. He paid for the hotel room, the meals and he was surprised to receive a 30 USD extra bill for cooking oil, (1USD/a day for oil to fry fish) Question 36. My uncle’s hobby is __________________________. A. writing B. talking C. playing D. fishing Question 37. He often catches a lot of fish ________________ he only keeps the big ones. A. Although C. but B. if D. so Question 38. Fishing is ______________ the inspiration for him to write stories. A. His hobby but also B. Not only his hobby but also C. Not his hobby but also D. Not only hobby but also Question 39. Why were the guests at the hotel happy? A. Because they stayed in a cheap hotel. B. Because they ate the fresh fish every day. C. They didn’t have to pay for the meals. D. They received the fresh fish from my uncle every day. Question 40. My uncle had an extra pay for the hotel because _______________. A. He ate fish every day. B. He used the cooking oil. C. He caught a lot of fish D. The chef used the cooking oil to fry the fish he gave to the kitchen.