TRẢ LỜI CHO EM BÀI NÀY ĐÚNG HAY SAI THÔI NHA: Đề bài: Hai ô tô xuất phát cùng một lúc và đi ngược chiều nhau từ hai tỉnh A và B cách nhau 230km. Sau 2 giờ thì hai xe gặp nhau. Tính vận tốc của mỗi ô tô biết rằng vận tốc ô tô đi từ A hơn vận tốc ô tô đi từ B là 5km/h. Bài giải: Gọi x (km/h) là vận tốc của ô tô đi từ B (x>0) Vận tốc của ô tô đi từ A là : x+5 (km/h) Quãng đường mà ô tô đi từ B đi đc dài : 2x (km) Quãng đường mà ô tô đi từ A đi đc dài : 2(x+5) (km) Vì lúc 2 xe gặp đc nhau thì tổng quãng đường của 2 xe đã đi đc cũng chính bằng quãng đường AB nên ta có PT : 2x + 2(x+5) = 230 2x + 2x + 10 = 230 2x + 2x = 230 - 10 4x = 220 x = 55 (tmđk) Vận tốc của ô tô đi từ B là 55 (km/h) Vận tốc của ô tô đi từ A là : 55+5 = 60 (km/h)

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Choose the letter A, B, C or D to complete the sentences with given words Question 1: Tokyo/ most populous/ capital/ city/ world. A. Tokyo is the most populous capital city in the world. B. Tokyo is most populous capital city in the world. C. Tokyo are the most populous capital city in the world. D. Tokyo are most populous capital city in the world. Question 2: She/ be/ to Dubai/ three times/ year. A. She is to Dubai three times this year. B. She is to Dubai three times year. C. She has been to Dubai three times year. D. She has been to Dubai three times this year. Question 3: Singapore/ located/ Southeast Asia. A. Singapore is located in Southeast Asia. B. Singapore was located in Southeast Asia. C. Singapore is located on Southeast Asia. D. Singapore was located on Southeast Asia. Question 4: It’s/ fantastic/ spend/ a day/ New York. A. It’s fantastic to spend a day in New York. B. It’s fantastic spending a day in New York. C. It’s fantastic to spend a day at New York. D. It’s fantastic spending a day at New York. Question 5: Many/ tourists/ visit/ Hanoi/ year. A. Many tourists visited Hanoi every year. B. Many tourists visit Hanoi every year. C. Many tourists will visit Hanoi every year. D. Many tourists has visited Hanoi every year. Question 6: Tokyo/ population/ 12/ million A. Tokyo has the population of 12 million. B. Tokyo has a population of 12 millions. C. Tokyo grows the population of 12 million. D. Tokyo has a population of 12 million. Question 7: My family/ visit/ Tower/ London tomorrow. A. My family going to visit the Tower of London tomorrow. B. My family is going to visit the Tower of London tomorrow. C. My family is visiting the Tower of London tomorrow D. My family is going visit the Tower of London tomorrow Rearrange the sentences to make meaningful sentences Question 8: world/ the/ longest/ is/ The/ Thai name/ in/ the/ of/ Bangkok. A. The Bangkok of Thai name is the longest in the world. B. The Thai name of the longest is Bangkok in the world. C. The Thai name of Bangkok is the longest in the world. D. The Bangkok is the longest Thai name of in the world. Question 9: been to/ is/ What/ destination/ exciting/ you/ have/ the most? A. What destination you is the most exiting have been to? B. What is the most exiting destination you have been to? C. What you have been to is the most exiting destination? D. What is the most you have been to exiting destination? Question 10: You/ the Statue of Liberty/ when/ should/ visit/ visiting/ New York.

C. READING I. Choose the word or phrase among A, B, C or D that best fits the blank space in the following passage. In Western countries, electricity, gas, and water are not (1) but necessities. Companies now realize that consumers want (2) that will not only work effectively, (3) save money. For most North American households, lighting (4) for 10 percent to 15 percent of the electricity (5) . However, this amount can be (6) by replacing an ordinary 100- watt light bulb with an energy-saving bulb. These bulbs use a (7) of the electricity of standard bulbs and last eight times (8) . Therefore, consumers can save about US$7 to US$21 per bulb. In Europe, there is a labeling scheme for refrigerators, freezers, washing machines and tumble dryers. The label tells the consumers how muchenergy efficiency each model has, compared (9) other appliancesin the same category. Ultimately, these innovations will save money as well as (10) the earth’s resources 1. A. launching B. luxuries C. coming D. peaking 2. A. tickets B. weapons C. spaceships D. products 3. A. but also B. towards C. with D. into 4. A. as good as B. like as C. accounts D. such as 5. A. burnt B. bill C. went off D. banged 6. A. reduced B. audience C. observatories D. watcher 7. A. sent back B. returned to C. separated from D. quarter 8. A. weightlessness B. longer C. wavelengths D. length 9. A. space B. atmosphere C. with D. universe 10. A. conserve B. drivers C. tourists D. astronauts II. Read the passage, and choose the correct answer A, B, C or D for each question. Almost all our energy comes from oil, coal, and natural gas. We call them fossil fuels. The earth’s fossil fuels are running out. What will happen when there is no oil, coal and gas on the earth? Scientists are trying to find and use other alternative sources of energy. We can use energy from the sun, the wind, and the water. Solar energy is unlimited. The sun supplies all the energy used to grow plants, to evaporate water for rain, and to maintain the temperate of the planet. All are necessary for human life. If we are able to collect solar energy, we will be sure to have this abundant source od power. 1. From which do plants on the earth get energy? A. stars B. the Mars C. the moon D. the sun 2. What are the other words or phrase for fossil fuels? A. natural gas B. oil C. coal D. oil, gas, natural gas 3. Natural sources of energy are energy from . A. wind B. the sun C. water D. the sun, wind, water 4. The word “abundant” in the passage is closet in meaning with . A. plentiful B. limited C. natural D. necessary 5. We are asking the question, “What will happen when there is no oil, coal, and gas on the earth?” because . A. we are now depending so much on oil, coal, and natural gas B. other sources of energy can come from the sun, wind, and water C. we are looking forward to seeing great changes D. we are looking for other alternative sources of energy D. WRITING I. Rewrite the sentences so that it has similar meaning as the sentence printed before, using the words given. 1. They will install solar panels on the roof of our house next week. → Solar panels 2. They will build a new school for poor children next month. → A new school 3. Will the plumber check cracks on the water pipes in two days? → Cracks 4. They sell these chemicals everywhere in my hometown. → These chemicals 5. They won't show the film on types of future energy sources next Friday. → The film 6. Some people will interview the new president on TV. → The new president 7. They will destroy the old thermal power plant at the end of this year. → The old thermal 8. They will widen the road to our village next year.