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viethoangnpt
2 năm trước
Câu 49. Một đu quay có bán kính 2 3 m lồng bằng kính trong suốt quay đều trong mặt phẳng thẳng đứng. Hai người A (coi như các chất điểm) ngồi trên một lồng của đu quay. Ở thời điểm t(s) người A thấy mình ở vị trí cao nhất và ở thời điểm t + 6 (s) lại thấy mình ở vị trí thấp nhất. Chùm tia sáng mặt trời chiếu theo hướng song song với mặt phẳng chứa đu quay và nghiêng một góc 60° so với phương ngang. Tốc độ cực đại của bóng người trên mặt đất bằng A. 2n/3 m/s. B. 4n/3 m/s. C. 3n/2 m/s. D. a/3 m/s. cái sin60 là sao vậy mọi người vẽ hình dùm mình với ??
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The Weekend Market Many tourists I have met have told me that one place they have to go is the weekend market. This market is huge and has everything from bags, souvenirs and handicrafts to many kinds of animal and many kinds of plants. It also has a fantastic variety of local food. In other words, the weekend market is a great place for shopping and experiencing the local culture. The market is located near the city's main bus station so people come from all over the country to buy and sell goods. Moreover, it is also near a sky train station and a subway station which makes it very convenient for city people, especially young people who don't have cars. The market is very large and full of hundreds of small shops and stalls. Consequently, it can be confusing to get around. However, if you get lost, it is a good idea to look for the clock tower which is right in the middle of the market. It will help you find your way. When I walk into the market early on a Sunday morning there are people and cars and motorcycles everywhere. You have to be careful where you walk. Many people are bringing their goods to sell in big bags on carts and trolleys. In fact, you might even have to jump out of the sellers' way as they charge along the narrow walkways with their goods. In addition to the sellers, tourists and locals are pouring in looking for something to eat or ready to start shopping. As time goes by, the market gets more and more crowded and you have to start squeezing past people to keep moving. As you walk through the market you will experience many sensations. For example, there are many smells, scents and aromas. One moment you will be smelling the aromas of stir-friend cooking dishes from a small restaurant and the next you smell the scents of orchids and other flowers as you pass through the cooler and more relaxing garden section. Furthermore, walking deeper into the market, your eyes will have trouble recording so many products with their many colors, designs and sizes. After a while you may feel dizzy and look for a quiet place to have a rest and a refreshing drink. Fortunately, there are many small cafes and drink stalls selling fresh coconut juice, orange juice or iced water. To sum up, a day at the weekend market is both a day of shopping and a unique experience for your senses. It is a kind of magical journey that is great as a first experience for tourists and an escape from daily life for locals. Moreover, while it is usually hot and crowded, the atmosphere is friendly and good-natured. Question 1 Why is the weekend market a great place to go on the weekend ? _________________________________________________________________________________________ 2 Why can the market be confusing ? ___________________________________________________________________________ _________ 3 How might you feel when walking through the crowded parts of the market ? _____________________________________________________________________________________ 4 What do you have to be careful about as you walk through the market ? ____________________________________________________________________________________ 5 Why is the market described as a “magical journey” ? __________________________________________________________________________________

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