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congqwer1042002
2 năm trước
Các bạn giúp mk giải câu này vs ạ: Từ thông quá 1 mạch kín biến thiên từ 0,1Wb tới 0,02Wb thì trong mạch xuất hiện một xuất điện động cảm ứng có giá trị 20V. Thời gian từ thông biến thiên là?
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New York is called “the Big Apple”. Maybe it is not exactly like an apple, it’s certainly very big. There are too many people, that’s the problem. The streets are always full of cars and trucks; you can never find a place to park. Travelling around is never easy in the city. If you have enough money, you can take a taxi. New York cabs are yellow. They look all the same. But the drivers are very different. Some were born and raised in New York, but many are newcomers to the United States. A few drive slowly, but most go very fast. Cab driving is a difficult job. It can be dangerous, too. Thieves often try to steal the drivers’ money. Drivers sometimes get hurt. If you don’t want to take a taxi, you can go by bus or you can take the subway. The subway is quick and it’s cheap, but some of its parts are old and dirty. Lights don’t always work and there are often fires on the track. On some subway lines, there are new, clean and silver trains. But you can’t see the color of the old trains easily. There is too much dirt and too much graffiti, inside and outside. Câu 22:What is the problem in New York? A.It looked like an apple B.It has too many apples. C.It is too long D.It is too crowded. Câu 2:You may find it hard to see _____. A.new, clean and silver trains B.drivers C.the color of the old trains D.newcomers Câu 5: What does “a cab” mean? A.truck B.a plane C.a taxi D.a bus Câu 33:Cab drivers in New York _____. A.can be dangerous B.look the same C.can be attacked by thieves D.were all born in New York Câu 18:. The word “subway” can be replaced by ____. A.platform B.light bulb C.Underground D.station

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