Có 150g dung dịch chứa 40g muối. Ta phải thêm bao nhiêu gam nước nữa dể dung dịch có tỉ lệ 20% muối

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Mark the letter A, B, C , or D on your answer sheet to indicate the correct answer to each of the following questions 26. Not only……………….the exam but she also got a scholarship. A. dis she pass B. she passed C. she has passed D. has she passed 27. he was the first person…………….the room. A. entering B. to enter C. to be enter D. having entered 28. Unfortunately, the company closed down because it couldn’t keep…….with rapidly changing technology. A . speed B. time C. fast D. pace 29. The climate of China is similar in many ways to…………………A. that of the United States B. which of the United States C. the United States D. this of the United States 30. Western women are more ……………… than Asian women. A. depend B. independent C. independently D. dependence 31. The twins look so much alike that no one can……………them……………. A. take/ apart B. tell/ away C. tell/ apart D. take/ on 32. The teacher always………….that the students make an outline before writing a complete essay. A. reports B. recommends C. tells D. says 33. I have no patience with gossips. What I told Bill was a secret. He………………it to you. A. mustn’t read B. shouldn’t have repeated C. mustn’t have repeated D. shouldn’t read 34. ……..he was kidnapped by the Iraqui guerrillas yesterday has been confirmed. A. That B. What C. If D. Unless 35. Air pollution poses a………………..to both human health and our environment. A. jeopardy B. difficulty C. problem D. threat 36. The people who……………the survey said that they had examined over 1,000 accidents. A. gave B. proceed C. set D. conducted 37. The teacher had some exercise……….at home yesterday so that he can correct them today. A. be done B. to be done C. being done D. done