Ba nguyên tử R kết hợp với 2 nhóm (PO4) tạo ra phân tử chất A. Trong phân tử, R chiếm 68,386% khối lượng. Kí hiệu hóa học của nguyên tố R là bao nhiêu ?

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71. “I don’t think John will come”, said Bill => Bill doubted…………………………………………………………….. 72. The postman was bitten by our dog. => Our dog…………………………………………………………………. 73. We couldn’t drive because of the fog. => The fog prevented………………………………………………………. 74. Although his leg was broken he managed to get out of the car. => In spite………………………………………………………………….. 75. The cake was so hard so I couldn’t cat it. => It was……………………………………………………………………. 76. We didn’t go because it rained. => If it hadn’t……………………………………………………………….. 77. I can’t cook as well as my mother does. => My mother………………………………………………………………... 78. I don’t suppose you have change for a pound, do you? => Do you happen…………………………………………………………… 79. He failed to win the race. => He didn’t…………………………………………………………………. 80. Mary rang hours and hour ago. => It’s hours…………………………………………………………………. 81. I’m sorry that I didn’t finish my homework last night. => I wish…………………………………………………………………….. 82. She asked Michael how she liked her new dress. => “How…………………………………………………………………….. 83. A train leaves at 8 o’clock every morning. => There is………………………………………………………………….. 84. Nobody can deny that she has a beautiful voice. => It………………………………………………………………………… 85. I would like you t help me to put the chairs away. => Do you mind……………………………………………………………. 86. The child will die if nobody sends for a doctor. => Unless…………………………………………………………………… 87. He would prefer you to pay him immediately. => He’d rather……………………………………………………………… 88. The water was so cold that the children couldn’t swim in it. => The water was not..................................................................................... 89. Somebody repaired her car yesterday. => She............................................................................................................ 90. You must see the manager tomorrow morning. => You’ve....................................................................................................... 91. There was never any answers when we rang. => Every......................................................................................................... 92. That’s an insulting name to use for him. => Don’t call.................................................................................................. 93. John asked if it was the blue one or the green she wanted. => Which........................................................................................................ 94. She liked Paris very little, and Rome less. => She thought Rome..................................................................................... 95. I can meet you if you arrive before eleven. => So.............................................................................................................. 96. They will catch all the prisoners again by tonight. => All the prisoners........................................................................................ 97. I’ve warned you not go to near that dog. => I’ve warned you about.............................................................................. 98. No, please don’t tell him. => I’d rather.................................................................................................... 99. Why don’t asked her yourself? => I suggest....................................................................................................

1. “ Why don’t you put better lock on the door,Barbara”? said John => John suggested.................................................................................................. 2. Although his both legs were broken in the crash, he managed to get out of the car before it exploded. => Despite his........................................................................................................ 3. I haven’t eaten this kind of food before. => This is the first............................................................................................ 4. The architect has drawn plans for an extension to the house. => Plans............................................................................................................... 5. It isn’t necessary for you to finish by Saturday => You.................................................................................................................. 6. “ How many survivors are there?”, asked the journalist. => The journalist wanted to know........................................................................ 7. It was such rotten meat that it had to be thrown away. => The meat was................................................................. 8. It is essential that Professor Van Helsing is met at the airport. => Professor Van Helsing................................................................................ 9. You can’t visit the USA unless you have a visa. => If you................................................................. 10. “ Can I borrow your typewriter,Janet”? asked Peter. => Peter asked if....................................................................... 11. She started working as a secretary five years ago. => She has.............................................................................. 12. She knows a lot more about it than I do. => I don’t know............................................................................... 13. My French friend finds driving on the left difficult. => My French friend isn’t............................................................................ 14. They think the owner of the house is abroad. => The owner..................................................................................... 15. We didn’t go on holiday because we did not have enough money. => If we................................................................................................. 16. The children couldn’t go swimming because the sea was rough. => The sea was too.................................................................................. 17. The mechanic serviced my car last week. => I............................................................................................ 18. I’m always nervous when I travel by air. => Traveling........................................................................................................ 19. He couldn’t afford to buy the car. => The car........................................................................................................... 20. “Why don’t you put your luggage under the seat?” he asked. => He suggested...................................... 21. Although he had a good salary, he was unhappy in his job. => In spite of............................................................................................ 22. I’m sorry I missed your birthday party. => I wish......................... 23. They haven’t cleaned the streets this week. => The streets................ 24. Apples are usually cheaper than oranges. => Apple are not................... 25. I advice you to put your money in the bank. => You’d........................ 26. That restaurant is so dirty that no one wants to eat there. => It is such......................................... 27. I’ll pick the children up if you like. => Would you..................................... 28. He objected to the fact that his secretary came to work late. => He was annoyed............................... 29. Tom is the most industrious pupil. => No other pupil................. 30. She isn’t accustomed to life in London => She’s not used to.......................