lập công thức hóa họcvà tính phân tử khối của hợp chấtcó phân tử na nần lượt lên kết với a,Cl b, nhóm (SO4)

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21. When questioned about the Government’s defence plans, the Minister gave very little _____________. A. out B. up C. away D. off 22. The child was told to eat all his vegetables or ____________ he would get no ice cream. A. in case B. in fact C. instead D. else 23. Even very young children are sensitive ___________ grammatical information. A. for B. to C. about D. with 24. There was a sudden ______________ of anger in the General’s eyes as he listened to the soldier’s report. A. fire B. flash C. flame D. shade 25. When Sarah ____________ from university next year, she ____________ English for nearly four years. A. graduates – will have been studying B. will graduate – will have been studying C. graduates – has been studying D. will graduate – has studied 26. I’m starving! I could eat like a ____________. A. cow B. horse C. house D. pig 27. Losing my job was a great shock, but I think I’m ____________ it. A. seeing to B. getting over C. standing for D. putting up with 28. “Excuse me. Is anyone sitting here?” – “___________________” A. Yes, I have been here for 15 minutes B. No, no, of course not. C. My friend is coming. D. But I’d like to be myself. 29. You shouldn’t walk around with ____________ feet. The floor isn’t very clean. A. naked B. stripped C. nude D. bare 30. At the advent of his speech, he told a joke but the audience failed to laugh. What is the closet meaning of the underlined word? A. end B. commencement C. creation D. climax