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loga1010
2 năm trước
Một người đạp xe từ từ lên dốc. Khối lượng của người và xe là 70kg, độ cao từ chân dốc lên đến đỉnh dốc là 200 m, độ dài quãng đường lên dốc là 4km. Tính lực tác dụng kéo xe chuyển động do người tạo ra khi xe lên dốc là bao nhiêu? Biết rằng lực cản chuyển động của xe không đáng kể.
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Read the following passage and choose the best answer by circling A, B, C or D.(1p) One custom that gives insight into people’s history and values is the way they greet one another. There is a wide range of greetings around the world. These range from the common handshake to other strange rituals found in some countries. Let’s take a look at how the simple action of greeting someone differs greatly from place to place. In the United States and Canada, for example, a simple handshake or nod is the norm. The handshake has an interesting origin: it started long ago as a way of showing people that you weren’t carrying a weapon. Shaking the person’s right hand while looking him or her in the eye is the usual method. Handshakes are also common in other parts of the world, including Britain and Russia. In Russia, males grasp other men’s hands very strongly during the handshake. Handshakes are also how most people in New Zealand greet each other. However, the native Maori people of that country display more physical contact: they press their noses together in a sign of trust and closeness. In other countries, such as France and Belgium, hugging and kissing are more common when two people meet. In those cultures, people kiss each other on the cheeks. The number of times varies depending on the particular country. In Saudi Arabia, men might hug and kiss each other (but not a woman) on the cheek. Men will also shake hands with other men there. In some Eastern countries, including Korea and Japan, bowing is the traditional greeting. In Japan, the deeper the bow, the deeper the respect shown. The strangest custom, though, is likely in Tibet. People there opt to stick out their tongue to greet others. 21.What is this reading mainly about? A. The importance of handshakes all around the world B. The origins and histories of various greetings C. The strangest types of greetings on Earth. D. The wide range of greeting customs in the world 22. Which of the following sentence is TRUE? A. People in Russia, but not England, shake hands B. The number of times people kiss on the cheek varies C. In the past, people noddedif they weren’t carrying aweapon D. You shouldn’t look at people when shaking their hands in the United States 23. How do most people in New Zealand greet each other? A. With a handshake B. By pressing noses together C. With a kiss on the cheek D. By sticking cut their tongue 24. What can be inferred about getting customs in Saudi Arabia? A. Men shake hands with women when meeting them for the first time B. It’s not proper for men to kiss women when they meet C. Women do not kiss other women when they meet D. Women can kiss men, but men can’t kiss women when they meet.

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