Chứng minh :1/2 mũ 2+1/2 mũ 3+1/2 mũ 4+......+1/2 mũ n <1

Read the passage carefully, then choose the correct answers. The latest addiction to trap thousands of people is the Internet, which has been blamed for broken relationships, job losses, financial ruin, and even suicide. Psychologists now recognize Internet Addiction Syndrome (IAS) as a new illness that could cause serious problems and ruin many lives. IAS is similar to other problems like gambling, smoking and drinking: addicts have dreams about the Internet; they need to use it as the first thing in the morning; they lie to their parents and partners about how much time they spent online; they wish they could cut down, but are unable to do so. A recent study found that many users spend up to 40 hours a week on the Internet. Some of the addicts are teenagers who are already hooked on computer games and who find it very difficult to resist the games on the Internet. Internet addicts find it hard ___________. A: to spend more time on the Internet B: to spend less time on the Internet C: to lie about the time they spent online D: to use the Internet in the morning 3 Read the passage carefully, then choose the correct answers. The latest addiction to trap thousands of people is the Internet, which has been blamed for broken relationships, job losses, financial ruin, and even suicide. Psychologists now recognize Internet Addiction Syndrome (IAS) as a new illness that could cause serious problems and ruin many lives. IAS is similar to other problems like gambling, smoking and drinking: addicts have dreams about the Internet; they need to use it as the first thing in the morning; they lie to their parents and partners about how much time they spent online; they wish they could cut down, but are unable to do so. A recent study found that many users spend up to 40 hours a week on the Internet. Some of the addicts are teenagers who are already hooked on computer games and who find it very difficult to resist the games on the Internet. The word ‘it’ in paragraph 2 refers to ___________. A: computer B: IAS C: dream D: the Internet 4 Choose the underlined part A, B, C or D that needs correcting. Picture 4 A: A B: B C: C D: D 5 Choose the word whose underlined part is pronounced differently from the others. A: out B: sound C: enough D: found 6 Read the passage carefully, then choose the correct answers. The latest addiction to trap thousands of people is the Internet, which has been blamed for broken relationships, job losses, financial ruin, and even suicide. Psychologists now recognize Internet Addiction Syndrome (IAS) as a new illness that could cause serious problems and ruin many lives. IAS is similar to other problems like gambling, smoking and drinking: addicts have dreams about the Internet; they need to use it as the first thing in the morning; they lie to their parents and partners about how much time they spent online; they wish they could cut down, but are unable to do so. A recent study found that many users spend up to 40 hours a week on the Internet. Some of the addicts are teenagers who are already hooked on computer games and who find it very difficult to resist the games on the Internet. What is the best title of the passage? A: Impact of Internet on teens B: A guide to the Internet C: The advantage of the Internet D: Hooked on the Net

8 người làm xong 1 đoạn đường trong 6 ngày.câu hỏi là 4 ngày thì cần mấy người để làm xong đoạn đường.

V. Use the correct form of the verbs: Yesterday (be)………. Sunday, Nam (get)……………up at six. He (do) ………..his morning exercises. He (take) ……………a shower, (comb)…………..hair, and then he (have) ………….. breakfast with his parents. Nam (eat)………… a bowl of noodles and (drink) ………a glass of milk for his breakfast. After breakfast, he (help) …………..Mom clean the table. After that, he (brush)………. his teeth, (put)………. on clean clothes, and (go)………… to his grandparents' house. He (have) …………..lunch with his grandparents. He (return) to his house at three o'clock. He (do)…………..his homework. He (eat)………. dinner at 6.30. After dinner, his parents (take)………. him to the movie theater. It (be)……………a very interesting film. They (come) …………..back home at 9.30. Nam (go)………………. to bed at ten o'clock. 1. What day was yesterday? …………………………………………………………………… 2. What time did Nam get up? ………………………………………………………………… 3. What did he do after breakfast? ………………………………………………………………. 4. Who did he have lunch with? ………………………………………………………………... 5. What time did he have dinner? ……………………………………………………………….. 6. What time did Nam go to bed ? ……………………………………………………………… VI. Write complete sentences. Use the past simple of the verbs. 1. I/ go swimming/ yesterday. =>................................................................................................................................................. 2. Mrs. Nhung/ wash/ the dishes. =>................................................................................................................................................ 3. my mother/ go shopping/ with/ friends/ in/ park. =>................................................................................................................................................ 4. Lan/ cook/ chicken noodles/ dinner. =>............................................................................................................................................... 5. Nam/ I/ study/ hard/ last weekend. =>................................................................................................................................................ 6. my father/ play/ golf/ yesterday. =>............................................................................................................................................... 7. last night/ Phong/listen/ music/ for two hours. =>.............................................................................................................................................. 8. they/ have/ nice/ weekend. =>............................................................................................................................................... 9. she/ go/ supermarket yesterday. =>.............................................................................................................................................. 10. We/ not go/ school last week. =>.............................................................................................................................................

Đại cáo bình Ngô có sự kết hợp hài hòa yếu tố chính luận và yếu tố văn chương, anh (chị) hãy phân tích để làm sáng tỏ nhận định này về các mặt: kết cấu, lập luận, nghệ thuật sử dụng từ ngữ, xây dựng hình tượng, nghệ thuật sử dụng câu văn, nhịp điệu.

Liên Xô,các đồng minh Mĩ,Anh, nhân dân các dân tộc có vai trò như thế nào trong việc tiêu diệt chủ nghĩa phát xít, kết thúc Chiến tranh thế giới II

1. Farmers are always faced with ......................... brought about by typhoons, floods or droughts. (destroy) 2. They made a decision to close down the factory ... ..................... . (permanence) 3. She was .. ...................... for days after the accident. (conscious) 4. A few passengers received serious . ....................... in the accident. (injure) 5. Children often feel a lot of .. ...................... about their first day at school. (anxious) 6. He drinks a lot of coffee to keep him .. ...................... . (wake) 7. Linda is one of the . ....................... from Friends of the Earth. (represent) 8. Attractive . ....................... can help to sell products. (package) 9. These products are ... ..................... friendly. (environment) 10. It’s difficult to find . ....................... at busy time. (accommodate) c. Supply the correct form of the verbs in the brackets: (5 0,2=1.0 pt) 1. When the phone rang, I (water) …………………the flowers in the garden. 2. You should practice ( speak) ……………………English everyday. 3. It (get) ……………………………………hotter and hotter in June. 4. His doctor advised him (give) ……………. Up somoking. 5. My uncle (not visit)............................. us since he (move) …………… to the new town. d. Fill in the blanks with the correct prepositions: (5 0,2=1,0 pt) 1. Instead.............. going to the theater, we'll go to the concert. 2. There is nothing to prevent the children............. playing there. 3. They will be here............... a few minutes. 4. Most children often participate................... outdoor activitives in their free time. 5. You are very different ............... your brother.

Giúp mình với : Số ha lớp 7A thích thể thao , âm nhạc , thời trang lần lượt tỉ lệ là2;3;5 . Biết số hs thích thời trang nhiều hơn số hs thích âm nhạc là 6 . Hỏi lớp 7A có bao nhiêu hs thích thể thao , âm nhạc , thời trang

II. Use the words and phrases to complete sentences. 1. The lakes/ are full/ rubbish. We should/ ask our friends/ clean them this Sunday. _____________________________________________________________ 2. The hurricane/ was terrible. Many houses/ are destroyed/ many people became homeless. ___________________________________________________________ 3. They are cold/ hungry. They have/ live/ the street this winter. We should ask people/ help them. ___________________________________________________________ 4. We/ can cook meals/ bring them/ homeless people. _____________________________________________________________ 5. We can ask people/ donate warm clothes/ help them/ rebuild their houses. _____________________________________________________________ 6. Yesterday I/ go to school late because I/ miss the bus. _____________________________________________________________ 7. Do you like/ work with children/ or with elderly people? _____________________________________________________________ 8. It’s good/ donate blood because you/ can save people’s lives. _____________________________________________________________ III.Use the cues to make sentences in the present perfect. 1. I/ buy/ a laptop/ but I/ not use/ it. _____________________________________________________________ 2. I/ write/ a blog/ but I/ not upload/ any photos to it. _____________________________________________________________ 3. We/ start/ the game/ half an hour ago/ hut we/ not finish/ it. _____________________________________________________________ 4. My dad/ be/ to London/ but he/ not see/ Big Ben. _____________________________________________________________ 5. I/ read/ my English book/ but I/ not do/ my English homework. _____________________________________________________________ 6. They/ have/ lunch/ but they/ not have/ dinner. _____________________________________________________________ 7. I/ download/ some songs/ but I/ not listen/ to them. _____________________________________________________________

Cho 4 lọ đựng riêng biệt: nc cất, dung dịch NaOH, dung dịch h2SO4, dung dịch NaCL. Bằng cách nào có thể nhận biết từng chất trg lọ.