Helpppppppppp😭 Hợp chất khí với hiđro của một nguyên tố là RH4 . Oxit cao nhất của nó chứa 53,3% oxi về khối lượng. Tìm nguyên tử khối nguyên tố đó.

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Mark the letter A, B, C, or D on your answer sheet to indicate the option that best completes each of the fol¬lowing exchanges. 16. David is apologising to his teacher for being late. - David: “Sorry I’m late! The traffic is so heavy.” - Teacher: “____________. Come in and sit down.” A. You’re so kind B. It’s alright C. Me neither D. Thank you 17. Peter and Mary are talking about social networks. - Peter: “Using social networks may have negative effects on students.” - Mary: “____________. It distracts them from their studies.” A. I’m not sure about that B. I don’t quite agree C. You’re wrong D. That’s quite true 18. Linda and Peter are talking about safe driving. - Linda: “I think drink-driving should be severely punished.” - Peter: “____________. It may cause accidents or even deaths.” A. You must be kidding B. I don’t think so C. I don’t understand what you mean D. I absolutely agree with you 19. A porter is talking to Mary in the hotel lobby. - Porter: “May I help you with your suitcase?” - Mary: “____________” A. What a shame B. Me too C. You’re welcome D. Yes, please 20. John is having dinner at Linda’s house. - John: “This roast beef is so delicious.” - Linda:”____________” A. sure. I’d love to B. I’m glad you like it. C. No, don’t worry. D. I don’t either. 21. Joana and David, two lectures, are talking about library skills. - Joana: “I think we should teach our students how to use the library.” - David:”____________ A. You’re absolutely wrong B. You must be kidding C. I couldn’t agree with you more D. That’s not a good idea 22. A shop assistant is talking to a customer. - Shop assistant: “Do you need anything else?” - Customer:”____________” A. That’s all. Thanks B. Good job! C. With pleasure D. You’re welcome 23. Ann and Peter are talking about housework. - Ann: “ I think children should be paid for doing the housework.” - Peter: “____________. It’s their duty in the family.” A. That’s what I think B. You’re exactly right C. There’s no doubt about it D. I don’t think so 24. Ken and Tom are high-school students. They are discussing where their study group will meet. - Ken: “Where is our study group going to meet next weekend?” - Tom: “____________.” A. Studying in a group is great fun. B. We are too busy on weekdays. C. Why don’t you look at the atlas? D. The library would be best. 25. Mike and Lane are university students. They are talking about Lane’s upcoming high-school reunion. - Mike: “So, you have your fifth high-school reunion coming up?” - Lane: “…………………….” A. Oh, the school reunion was wonderful. B. No. You’re in no mood for the event. C. The food at the reunion was excellent. D. Yeah. I’m really looking forward to it. 26. A waiter in a restaurant is talking to a customer who has just finished his meal there. - Waiter: “Here’s your bill, sir.” - Customer: “____________” A. Don’t mention it. B. Can I pay by credit card? C. What do you have? D. You’re welcome. 27. Two close friends Tom and Kyle are talking about Kyle’s upcoming birthday. - Tom: “Can I bring a friend to your birthday party?” - Kyle: “____________” A. It’s my honour. B. Let’s do it then. C. The more the merrier. D. That’s right. 28. Two friends Diana and Anne are talking about Anne’s new blouse. - Diana: “That blouse suits you perfectly, Anne.” - Anne: “____________’’. A. Never mind. B. Don’t mention it. C. Thank you. D. You’re welcome. 29. Mary is talking to a porter in the hotel lobby. - Porter: “Shall I help you with your suitcase?” - Mary: “____________” A. Not a chance. B. That’s very kind of you. C. I can’t agree more. D. What a pity! 30. Susan accidentally stepped on Denise’s foot. - Susan: “Oops! I’m sorry, Denise.” - Denise: “____________” A. You shouldn’t do that. B. It’s alright. C. You are welcome. D. It’s nonsense. 31. Hana and Jenifer are talking about a book they have just read. - Hana: “The book is really interesting and educational.” - Jenifer: “____________” A. I’d love it. B. That’s nice of you to say so. C. I couldn’t agree more. D. Don’t mention it. 32. Jolie and Tom are meeting at the supermarket. - Jolie: “Hi, Tom. How are you doing?” - Tom: “____________. How about you?” A. I’m waiting for my sister B. I’m shopping for food C. I’m doing nothing D. I’m doing well

BÀI TẬP ÁP DỤNG Mark the letter A, B, C, or D on your answer sheet to indicate the option that best completes each of the fol¬lowing exchanges. 1. Hung was invited to Hoa's party. He wants to thank her for the lovely party. Choose the most suitable response to fill in the blank in the following exchange. - Hung: "Thank you very much for a lovely party." - Hoa: "……………………….…….". A. Thanks B. Have a good day C. You are welcome D. Cheers 2. Mary has a special meal tonight. She has just made friend with Steven, so she wants to invite him to have dinner with her. Choose the most suitable response to fill in the blank in the following exchange. - Mary: “ Would you like to have dinner with me?” - Steven: “ …………………………” A. Yes, it is. Isn’t it? B. Yes, I’d love to C. Yes, so do I D. I’ve had enough 3. John was in Hanoi and wanted to send a parcel to his parents. He asked a local passer-by the way to the post-office. Choose the most suitable response to fill in the blank in the following exchange. - John: “Can you show me the way to the nearest post office, please?” - Passer-by: “…………………………….” A. Not way, sorry. B. Just round the corner over there. C. Look it up in a dictionary! D. There’s no traffic near here. 4. Lora has just bought a new skirt that she likes very much. Choose the most suitable response to fill in the blank in the following exchange. -Jane: “You look great in that red skirt, Lora!” -Lora: “ ………………………………” A. No, I don't think so. B. Oh, you don't like it, do you? C. Thanks, I bought it at Macy’s. D. Thanks, my mum bought it. 5. Ken and Tom are high-school students. They are discussing where their study group will meet. Ken: “Where is our study group going to meet next weekend?” – Tom: “ ……………………...” A. Studying in a group is great fun. B. We are too busy on weekdays. C. Why don’t you look at the atlas? D. The library would be best. 6. Sue and Mira are talking about the use of mobile phone in class. Sue: “Students should not be allowed to use mobile phone in class.” Mira: “ ………………………. This will distract them from studying.” A. Not really B. No way! It’s useful C. I’m of the opposite opinion D. I quite agree 7. Jenny and Jimmy are talking about university education. - Jenny: “I think having a university degree is the only way to succeed in life.” - Jimmy: “ ………………….. There were successful people without a degree.” A. That’s all right. B. I don’t quite agree. C. I can’t agree more. D. That’s life. 8. Silas is talking to his roommate, Salah, about the Olympic Games. - Silas: “Do you think our country can host the Olympic Games some day in the future?” - Salah: “……………………….. We can’t afford such a big event.” A. No, I don’t think so. B. You can say that again. C. I can’t agree with your more. D. Yes, you’re right. 9. Lien was walking her dogs in the park, she met Lan accidentally. - Lan: “How lovely your pets are!” - Lien: “ ……………………………….” A. Thank you, it's nice of you to say so B. Really? They are C. Can you say that again D. I love them, too 10. Thorny enters the meeting room and sees a lot of men. He is asking one of the men near the door. - Thorny: “Excuse me. I don’t want to interrupt you but...” - The man: “…………………….………” A. What can I do for you? B. Certainly. How dare you! C. I quite agree D. I have no idea 11. Husha and Honish are talking about Trishie after watching her music performance. - Husha: “Trishie’s the best singer in our school.” - Honish: “………………………….” A. Yes, please. B. I couldn’t agree with you more. C. That’s OK! D. Yes, tell me about it. 12. Luca is at Noi Bai Airport. She wants to exchange some money, she is talking to Paula - a clerk at a currency exchange kiosk. - Luca: “I'd like to change some money.” Paula: “ ………………………………” A. Five tens, please B. Which currency? Loại tiền gì C. You haven't signed it. D. What's your account number? 13. Yuki and Hana are having a free afternoon. Yuki is inviting Hana to see a new movie with him. - Yuki: "Do you feel like going to the cinema this afternoon?" - Hana: “ ……………………………...” A. I don't agree. I'm afraid B. I feel very bored C. You're welcome D. That would be great 14. David is talking to Lucy about her painting. - David: “What a beautiful painting!” - Lucy: “____________” A. No problem B. It’s on the wall C. I’m glad you like it D. You’re welcome. 15. Peter and Dane are talking about environmental protection. - Peter: “We should limit the use of plastic bags.” - Dane: “____________. We can use paper bags instead.” A. I completely agree. B. It’s not true. C. I don’t quite agree D. You’re wrong.