mọi người giúp em giải chi tiết với ạ nếu ai trả lời trước ngày 10/4/2020 thì mình sẽ vote 5 sao cảm tạ Bài 3: Một khung dây hình tròn diện tích S=15cm vuông gồm N=10 vòng dây, đặt trong từ trường đều có hợp với véc tơ pháp tuyến của mặt phẳng khung dây một góc =300 như hình vẽ. B=0,04T. Tính độ biến thiên của từ thông qua khung dây khi: a.Tịnh tiến khung dây trong vùng từ trường đều. b.Quay khung dây quanh đường kính MN một góc 180độ c.Quay khung dây quanh đường kính MN một góc 360độ

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A Read the article about Conor’s friend, Antonio. This is my friend, Antonio. He’s 16 years old and he goes to my school. He’s from Spain and he used to live in Seville, but when he was nine his family came to livehere in York. His mum’s a doctor,she works atYork Hospital, and his dad teaches Spanish at York University. Antonio has got black hair and brown eyes. When he goes back to Spain on holiday, he always gets a tan. I never tan because I’m very pale. In the summer, I get lots of freckles. It’s great to spend time with Antonio and his family because they are very sociable and cheerful. His parents are really friendly and they always have delicious food because Antonio’s grandmother lives with them and she’s an excellent cook. When Antonio first came to our school, he was quite shy because he didn’t speak English very well and he often looked sad.But he’s very smart and a few months later, his English was so good people thought he was from York. Now Antonio never looks unhappy. He loves school and has got lots of friends. He likes to spend time with me and two or three close friends. We usually play football after school or we go to each other’s houses and just hang out together. We play video games, we watch TV and sometimes we play music together. Antonio is brilliant at singing, so last year we decided to start our own band. That’s me playing the guitar, and that’s Antonio singing. We have a drummer and a bass player too. Our dream is to be a well-known band in the future. We have to work hard and learn new songs, but that’s quite difficult because Antonio makes us laugh all the time. He loves telling jokes. I hope that Antonio stays in York for ever because he’s a great friend! B Complete the Exam Task. Exam Task Read the article again. Are sentences 1–8 ‘Right’ (A) or ‘Wrong’ (B)? If there is not enough information to answer ‘Right’ (A) or ‘Wrong’ (B), choose ‘Doesn’t say’ (C). 1 Antonio hasn’t got any brothers or sisters.  2 Antonio’s dad is a school teacher.  3 Conor has got blonde hair.  4 Antonio’s granny is brilliant at cooking.  5 Antonio is sometimes quite sad.  6 Some people think Antonio is English.  7 Conor has got four close friends.  8 Antonio and Conor want to be famous. 

Mark letter A, B, C or D on your answer sheet to indicate the sentence that is closest in meaning to the original sentence in each of the following questions. She prefers watching TV to reading books. A: She would rather watch TV to read books. B: She would rather watch TV than read books. C: She would rather watching TV to reading books. D: She would rather to watch TV than read books. 25 Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks. Air (23)…………..is the cause of ill-health in human beings. In a lot of countries, there are laws limiting the amount of smoke which factories can (24)…………..although there is not enough information on the effects of smoke on the atmosphere. Doctors have proved that air pollution causes lung diseases. The gases from the exhausts of cars also (25)………….. air pollution in most cities. The lead in petrol produces a poisonous gas, which is often (26)…………..in busy streets circled by buildings. Children who live in areas where there is (27)…………..lead in the atmosphere cannot think as quickly as other children, and are clumsy when they use their hands. Question 23. A: polluting B: pollute C: polluted D: pollution 26 Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions. Thousands of years before Columbus came to the New World, the American Indians entered North America by crossing a narrow strip of land that once connected Alaska and Siberia. The migrants entered a new world in which there were no people at all. But there were many animals to hunt, and there were forests where nuts, roots, and berries could be gathered. When the Europeans came to the New World, the Indians, at first, taught the settlers how to plant corn, bake fish, make canoes, and smoke tobacco. In return, the white introduced horses, guns, gunpowder, and alcohol. But at last, there were struggles for land, and the struggles could have only one result – war. When the wars were over, all Indians were moved to large tracts of land called reservations. Now, some of them, embittered by mistreatment, are determined to preserve their tribal life; some wish to modernize the reservations. These alternatives, with many variations, are what most Indians have chosen – a future in modern technology and education, or the revival of ancient tradition and treaties. The most accurate statement about contemporary Indian is ___________. A: some Indians preserve conventional life style. B: Some Indians preserve conventional life style and have adopted modern culture and technology". C: some Indians have adopted modern culture and technology. D: most Indians reject modern culture and technology. 27 Mark the letter A, B, C or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions. Picture 2 A: I’m B: usually C: am not D: I 28 Mark the letter A, B, C or D on your answer sheet to indicate the word CLOSEST in meaning to the underlined word in each of the following questions. Around 150 the Greek astronomer Hipparchus developed a system to classify stars according to brightness. A: shine B: record C: categorize D: diversify 29 Mark letter A, B, C or D on your answer sheet to indicate the sentence that is closest in meaning to the original sentence in each of the following questions, using the words in brackets. They think that he was a spy. (thought) A: It is thought to be a spy. B: It is thought that he had been a spy. C: He is thought to have been a spy. D: He is thought to be a spy. 30 Mark the letter A, B, C or D on your answer sheet to indicate the most suitable response to complete each of the following exchanges. Tom: Can I have a look at that pullover, please?” Sue: “_______” A: Sorry, it is out of stock. B: Which one? This one? C: Can I help you? D: It’s much cheaper.