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engin.huutho
2 năm trước
Chỉ cần làm ngắn gọn thôi mình hứa sẽ vote 5 sao Tổng số hạt cơ bản trong nguyên tử nhôm là 40; trong đó, số hạt không mang điện ít hơn số hạt mang điện là 12. Nhôm còn có một đồng vị khác với số notron ít hơn đồng vị nhôm ở trên 1 đơn vị.Hãy xác định kí hiệu nguyên tử của đồng vị này.
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chỉ cần đọc rồi khoanh thôi mà b. Read the passage and choose the best answer A, B, C or D I’m interested in sports, especially athletics, and I run seven or eight kilometers every day. I particularly enjoy cross country running, where you have to run across fields, jump over streams and so on. While I’m running I think about all sorts of things, and at the end of a run I’m sometimes surprised to find that I’ve managed to solve a problem that was on my mind. Next year, I’m going to try the London Marathon. It’s hard race 26 miles, or 42 kilometers-and you have to be tough to finish, but I very much want to do it. I worry a bit about getting too old, and I’d like to prove to myself that I’m still almost as fit as I was twenty years old. I’m interested in mountaineering as well as running. I’ll never become an expert climber, but I know what I’m doing in the mountains. I successfully completed a course in snow and ice climbing when I was younger; and I’ve done a series of easy climbs in the Alps during the last few years. My wife doesn’t share my interest in mountains. She agreed to go climbing with me once, but she found that she felt ill as soon as she got above 1,000 meters. 1. The word “particularly” in line 1 can be best replaced by…………. A. normally B. suddenly C. partly D. especially 2. At the end of a run the writer sometimes finds that…………. A. he gets the answer to a problem B. he grows bigger C. he feels better D. he gets a surprising problem 3. The writer wants to take part in the London Marathon because ……………. A. He wants to prove that he is still healthy B. he wants to do it before getting old C. the reward is great D. it helps him solve his problems 4. The writer’s wife is not interested in mountaineering because……………. A. it doesn’t bring her any benefit B. she feels ill at the height of above 1,000 meters C. she doesn’t want to climb together with her husband D. the weather in the mountains is too cold for her 5. According to the passage, which of the following statements is TRUE? A. The writer doesn’t practice any sports. B. The London Marathon is not an easy race. C. Becoming an expert climber has always been the writer’s dream. D. The writer knows very little about mountaineering.

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. During the teenage years, many young people can at times be difficult to talk to. They often seem to dislike being questioned. They may seem unwilling to talk about their work in school. This is a normal development at this age, though it can be very hard for parents to understand. It is part of becoming independent of teenagers trying to be adult while they are still growing up. Young people are usually more willing to talk if they believe that questions are asked out of real interest and not because people are trying to check up on them. Parents should do their best to talk to their sons and daughters about school work and future plants but should not push them to talk if they don't want to. Parents should also watch for the danger signs: some young people in trying to be adult may experiment with sex, drugs, alcohol, or smoking. Parents need to watch for any signs of unusual behaviour which may be connected with these and get help if necessary. Question 28: Why do adults sometimes find teenagers difficult to talk to…. A. because most teenagers are quiet B. because teenagers don't want to talk to other people. C. because teenagers think adults are not honest D. because most teenagers hate adults. Question 29: When can you expect young people to be more talkative than usual. A. When people talk to them because they are really interested and not just checking on them? B. When adults give them a lot money to spend. C. When adults talk to them about something other than their work in school. D. When adults talk to them about sex, alcohol and drugs. Question 30: Some teenagers experiment with drinking bad smoking because A. cigarettes and alcohol are available everywhere. B. cigarettes and alcohol are cheap C. women like smoking and drinking men D. they regard them as a mark of adulthood Question 31: The word BEHAVIOUR in the passage most nearly means A. feeling B. manners C. activities D. reaction Question 32: This passage is taken from a… A. handbook for parents B. school timetable C. teenage magazine. D. book for children Ai giúp em giải thích và làm bài với ạ, em hứa cho 5 sao và câu trả lời hay nhất ạ

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 blank. Today, there (23) __a TV set in nearly every home. People watch TV every day. Americans watch television about 35 hours a week. However, is television good (24) ___bad for you? People have different answers to this question. Some say that there is a lot of violence on TV today, the programs are terrible and people do not get any exercise (25) ___they only sit and watch TV. Others (26) ___that TV programs bring news from all over the world and help you learn many useful things. Thanks to TV people learn about life (27) __other countries, and it helps people relax after a long hard-working day. Question 23: A. are B. is C. was D. be Question 24: A. or B. but C. and D. so Question 25: A. though B. despite C. because D. so Question 26: A. talk B. think C. ask D. tell Question 27: A. at B. on C. in D. of Em cần gấp ạ ai làm và giải thích giúp em với ạ em hứa cho 5 sao

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