user-avatar
vothinhieu333
2 năm trước
Viết các biểu thức đại số để diễn đạt các ý sau a) Tổng của a và b bình phương
Thích Trả lời Chia sẻ

Các câu hỏi liên quan

31. You should_________ more time listening to English programs on the radio. A. take B. spend C. use D. save 32. The boy is playing chess_________ with his father. A. happy B. happiness C. happily D. unhappy 33. I_________ my best friend since 2015. A. haven’t seen B. haven’t see C. hasn’t see D. hasn’t seen 34. London is________ of England. A. capital B. a capital C. an capital D. the capital 35._______the newsreader on BBC News read very fast, my brother can hear everything in the news. A. But B. However C. Although D. And 36. Our people live________ than before the war. A. well B. the best C. as well D. better 37. ___________ did you spend in Ha Long Bay? – One week. A. How many B. How much C. How long D. How often 38. ______the birthday of Nam’s mother, he made her a big cake. A. In B. At C. On D. From 39. Solar energy doesn’t cause__________. A. pollution B. polluted C. pollute D. pollutant 40. That poem ________ by a famous writer in 1984. A. was writing B. wrote C. was written D. is written giúp mik vs

yêu cầu dẫn chứng nữa nhé 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 from 43 to 50. Carbon dating can be used to estimate the age of any organic natural material; it has been used successfully in archeology to determine the age of ancient artifacts or fossils as well as in a variety of other fields. The principle underlying the use of carbon dating is that carbon is a part of all living things on Earth. Since a radioactive substance such as carbon-14 has a known half- life, the amount of carbon-14 remaining in an object can be used to date that object. Carbon-14 has a half-life of 5,570 years, which means that after that number of years, half of the carbon- 14 atoms have decayed into nitrogen-14. It is the ratio of carbon-14 in that substance that indicates the age of the substance. If, for example, in a particular sample the amount of carbon-14 is roughly equivalent to the amount of nitrogen-14, this indicates that around half of the carbon-14 has decayed into nitrogen-14, and the sample is approximately 5,570 years old. Carbon dating cannot be used effectively in dating objects that are older than 80,000 years. When objects are that old, much of the carbon-14 has already decayed into nitrogen-14, and the miniscule amount that is left doesn’t provide a reliable measurement of age. In the case of older objects, other age- dating methods are available, methods which use radioactive atoms with longer half-lives than carbon has. Question 41: This passage is mainly about . A. archeology and the study of ancient artifacts B. one method of dating old objects C. various uses for carbon D. the differences between carbon-14 and nitrogen-14 Question 42: Which of the following is NOT true about carbon-14? A. It and nitrogen always exist in equal amounts in any substance. B. Its half-life is more than 5,000 years. C. It can decay into nitrogen-14. D. It is radioactive. Question 43: The word “it” in paragraph I refers to . A. carbon dating B. the age C. any organic natural material D. archeology Question 44: The word “underlying” in paragraph I could best be replaced by . A. below B. requiring C. serving as a basis for D. being studied through Question 45: The word “roughly” in paragraph 2 is closest in meaning to . A. precisely B. harshly C. approximately D. coarsely Question 46: The paragraph following the passage most probably discusses . A. what substances are part of all living things B. how carbon-14 decay intonitrogen-14 C. why carbon-14 has such a long half-life D. various other age-dating methods Question 47: It is implied in the passage that . A. carbon dating has no known uses outside of archeology B. fossils cannot be age-dated using carbon-14 C. carbon dating could not be used on an item containing nitrogen D. carbon-14 does not have the longest known half-life Question 48: It can be inferred from the passage that if an item contains more carbon-14 than nitrogen- 14, then the item is . A. not as much as 5,570 years old B. too old to be age-dated with carbon-14 C. too radioactive to be used by archeologists D. more than 5.570 years old Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best completes each of the following exchanges. Question 49: 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 Question 50: 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!

Câu 1: Có những lại ròng rọc nào? Mỗi loại ròng rọc đó giúp con người làm việc dễ dàng hơn như thế nào? Câu 2: Nêu các kết luận về sự nở vì nhiệt của chất rắn? II. Bài tập: Bài 1: Palăng là gì? Sử dụng palăng giúp ích cho con người trong việc nâng vật nặng lên cao như thế nào? Bài 2: Khi nhiệt độ của một vật rắn tăng lên thì: A, Thể tích của vật tăng lên. B, Khối lượng của vật tăng lên. C, Khối lượng riêng của vật tăng lên. D, Khối lượng riêng của vật giảm đi. Bài 3: Ba thanh đồng, nhôm, sắt, có chiều dài bằng nhau ở 100 0 C. Khi nhiệt độ của ba thanh cùng giảm xuống còn 50 0 C thì: A Chiều dài ba thanh vẫn bằng nhau. B. Chiều dài thanh nhôm lớn nhất. C. Chiều dài thanh đồng lớn nhất. D. Chiều dài thanh sắt lớn nhất. Bài 4: Khi nhiệt độ thay đổi, các trụ bêtông cốt thép không bị nứt. Em hãy cho biết vì sao? Bài 5: Một quả cầu bằng đồng bị kẹt trong một cái vòng bằng sắt. Để tách chúng ra, một HS đem hơ nóng cả quả cầu và chiếc vòng. Theo em bạn HS đó có tách được quả cầu ra khỏi vòng không? Tại sao? Bài 6: Có 2 cốc thủy tinh chồng khít vào nhau. Một HS định dùng nước nóng và nước đá để tách 2 cốc ra. Theo em, bạn đó phải làm thế nào? Bài 7: Vào mùa hè đường dây điện thường hay võng xuống nhiều hơn so với vào VnDoc - Tải tài liệu, văn bản pháp luật, biểu mẫu miễn phí mùa đông. Em hãy giải thích tại sao?

IIII.Change the active into the passive : 41*. He doesn’t like people laughing at him .-……………………………………………….... 42*. The workers want to change the manager .-…………………………………………........ 43. Did they build the garage at the same time as the house ? - …………………………………………………………………………………………… 44. They use cars and trucks to carry food to market .-………………………………….......... 45.Who invited her to the party last night ?-………………………………………………….. 46.You should not cut the flowers in the garden .-………………………………………......... 47.Has anyone ever asked you for your opinion ?-………………………………………......... 48.They paid me a lot of money to do the job .-………………………………………................ 49. No one told me about the change of the meeting. -………………………………..................................................................................................... 50.Tom used to visit his grandparents at weekends -……………………………………........................................................................................... 51.Did Sue knock that vase to the floor ?- ………………………………………........................ 52.What time can the boys hand in their papers ? -…………………………............................... 53.How long have they waited for the doctors ?-……………………………………................... 54.Who looked after the children for you ?-………………………………………..................... 55.Where do people speak English ? -………………………………………............................... 56.How did the police find the lost man ? -………………………………….............................. 57.They have given the women in most countries in the world the right to vote.(quyền bầu cử) -………………………………………………………………………………………… 58.People believe that 13 is an unlucky number. – It’s believed …………………………......../- 13 is believed ……………………………….. 59.They know that English is an international language. - It’s known that… ……………………………./- English is known ……………………….... 60.They say that John is the brightest student in class. – It’s said that … ……………………… /- John is said …………………........................ 61.Open your book. – Let ...........................……………………………………................... 62.Take off your hat . - Let …………………………………………………......................... 63.Don’t do that silly thing again . – Don’t let …………………………………. .................. 64* I don’t like people talking me what to do .-………………………………….................... 65* Don’t touch this switch . -……………………………………………………….............. 66. Are the police making iquires about the thief ? -………………………………….............................................................................................. 67.Will buses bring the children home ? -……………………………………......................................................................................... 68.What books are people reading this year ? -……………………………………………………………................................................... 69.Did your teacher teach you how to apply this theory ? - ................................................................................................................................................ 70.I had him repair my bicycle yesterday. - ……………………………………………………………..................................................

2018 © Loga - Không Ngừng Sáng Tạo - Bùng Cháy Đam Mê
Loga Team