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hanhn5987
2 năm trước
Khối lượng hạt nơtron là 1,6748.10-27 kg. Giải sử nơtron là các hạt hình cầu có bán kính là 2.10-15m. Nếu giả thiết xếp đầy nơtron vào một khối hình lập phương mỗi chiều 1 cm, khoảng trống giữa các quả cầu chiếm 26% thể tích hình lập phương. Hãy tính khối lượng của khối lập phương chứa hạt nơtron đó? Giúp mình với ạ
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Đề 1: I. Choose the word whose underlined part pronounced differently from the others: 1. A. sound B. cloud C. found D. favourite 2. A. crafts B. comics C. streets D. stamps 3. A. camel B. cattle C. paddy D. buffalo 4. A. lived B. loaded C. harvested D. populated II. Choose the best answer to complete each of the following sentences:(2,5 pts) 1. I don’t like………….up early in the winter days. I love……………in bed late. A. getting/ stay B. get/ stay C. getting/ staying D. get/ staying 2. My brother is learning to……………a horse at the moment. A. ride B. collect C. herd D. pick 3. …………….does Hoa Ban festival take place?- In Lai Chau A. What B. When C. How D. Where 4. Mai studies Maths a little bit……………… A. bad B. badly C. good D. smartly 5. Why don’t we………………our parents with some DIY projects?.- I think it’s useful A. do B. make C. help D. give 6. It is typical of the cultural life of………….Thai people. A. some B. a C. the D. x 7. The Viet people have many………………..customs and crafts. A. tradition B. traditional C. culture D. customary 8. The streets in the cities are………………than those in the countryside. A. crowded B. crowdeder C. more crowded D. less crowded 9. The ……………on display in Da Nang Museum of Cham Sculpture are very interesting. A. items B. goods C. products D. shows 10. Do you fancy………………around the West Lake with me this Sunday morning? A. having B. staying C. moving D. going III. Give the correct forms of the verbs: (1pt) 1. They adore (make)…………..and (eat)…………..good food. 2. I used to climb trees when I (be)………………small. 3. It is necessary (water)…………….the flowers twice a day. IV. Fill in the blank with the appropriate form of the word in brackets: (1pt) 1. It is very…………….for people in remote areas to get to hospitals. (CONVENIENT) 2. My sister doesn’t like surfing the Internet, she says it is…………….(BORE) 3. Our family has lived……………..in the country than in the town since last year. (HAPPY) 4. The………have a very hard life. They can not live permanently in one place. (NOMADIC) 5.The Tay people live mostly in the ............regions in the north of Viet Nam (MOUNTAIN) 6....................... you ever ................................a buffalo? (RIDE) V. Read the passage, then answer the questions: MY VILLAGE We are Khmer Krom, one of the biggest ethnic groups in the south of Viet Nam. We live by farming – mostly rice – and fishing on the Mekong River. Life is sometimes hard as our work depends heavily on the weather. When it is not harvest time, the men of the village go fishing from early morning and don’t return until late afternoon. By the time they return, most of the village women will be waiting for them on the river bank. They wait to buy the fish, which they will later sell at the local market or bring to the nearby town for a higher price. Our children will be there too. We love running around the beach and waiting for the boats to come in. Our most important festival of the year is the Chol Chnam Thmay, which celebrates the New Year. It falls in mid-April. Every family tries to prepare well for the festive activities. The community also visits and helps poor families so that everybody has a happy New Year. Questions: 1. Where do the Khmer Krom live? …………………………………………………………………………….. 2. Why is life hard for the Khmer? …………………………………………………………………………….. 3. When do the women and children of the village go to the river bank? …………………………………………………………………………….. 4. What do the women do with the fish they buy from the fishermen? …………………………………………………………………………….. VI. Write questions for the underlined parts in the following sentences: (1,5pts) 1. It is about seven kilometers from the centre to the Museum of Ethnology. ………………………………………………………………………………………? 2. The Tay People have the second largest population in Viet Nam. ………………………………………………………………………………………? 3. The Yao people are famous for their elaborate costumes. ………………………………………………………………………………………? VII. Rewrite sentences with the same meanings of the root ones: (1pt) 1. A sports car goes faster than an ordinary car.  An ordinary car goes………………………………………………………….. 2. He likes listening to pop music better than watching TV.  He prefers…………………………………………………………………….. VIII. Complete each second sentence so that it has a similar meaning to the first sentence. 1. His car runs fast but a race car runs faster. (as … as) → …………..…………………………….………………………….………….…… 2. He likes to listen to pop music than to watch TV after school. → He prefers ….……….……….……….………....................................................... 3. No one in my group is more intelligent than Long. → Long……….……….…….……….……….……………….….……….…………. 4.Thanks/TVandInternet/people/myvillage/have/more/fun/and/know/more/life/outside/village → .......................................................................................................................... 5.It/be/important/parents/be/aware of/what/children/doing online.

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