Một vật dđđh với phương trình x = 4cos( $\pi$t - $\frac{\pi}{6}$) với x tính bằng cm, t tính bằng s. Lấy $\pi^{2}$ = 10. Gia tốc của vật tại thời điểm t = $\frac{1}{2}$ s là: A. 2 cm/$s^{2}$ B. 20 cm/$s^{2}$ C. 2π cm/$s^{2}$ D. 10 cm/$s^{2}$

Giúp em vs ạ em cảm ơn nhiều 😘😘

Find the mistake in the four underlined parts of each sentence and correct it. 11. You mustn’t cheat in exams because the teacher will punish you when you do that. 12. I’m so worried because I mustn’t be at home after school right now. 13. It is more interesting book I have ever read. 14. What’s the better film you have ever seen? 15. You mustn’t look after the house when your parents are away 16. It is raining heavily outside. You shouldn't bring your raincoat. 17. She always give presents to her parents on Tet holiday. 18. She will helps her mother decorate the house before Tet. 19. I don't think that lucky money can bring us good and bad luck. 20. The New Year Festival in Thailand is on April. It is very hot.

giúp mik nha mik cần gấp nha .Làm bằng cột nha

từ 1 đến 201 có bao nhiêu số chia hết cho 3 và 5

Hoà tan hết 22,4g Fe trong 200g dung dịch axit HCl. Tính nồng độ phần trăm của dung dịch axit HCl.

Help me~! Mấy bạn giỏi Hóa giúp mình dzới! Hứa vote 5 sao + CTLHN + Cảm ơn

1. Xác định ngôi kể và nêu tác dụng việc sd ngôi kể đó. 2. Tr đoạn văn trên, hình ảnh nào khơi dậy kỷ niệm về buổi tựu Tr đầu tiên của Nv tôi¿ 3. Cảm nghĩ của em về vai trò của nhà Tr đối v mỗi hs ( 3-5dg)

III. Rewrite the sentences so that they have the same meaning as the original ones. 1. My foot was hurt. I managed to walk to the nearest village. (although) ________________________________________________________________ 2. I’ve been too busy to answer by email. I’ll do it soon. (nevertheless) ________________________________________________________________ 3. Did they go to school on foot? (Tag question) ________________________________________________________________ 4. A lot of people found the show boring. (bored) ________________________________________________________________ 5. Why don’t we collect the plastic bags on the beach this weekend? (What about) ________________________________________________________________ 6. I find English interesting. I am ______________________________________________________________ 7. They will install solar panels on the roof of our house next week. Solar panels _______________________________________________________ 8. People won’t burn fossil fuels for energy in the future. Fossil fuels ________________________________________________________ 9. New York has more billionaires than Tokyo. (fewer) ________________________________________________________________ 10. Jakarta doesn’t have as many skyscrapers as Shanghai. (more) ________________________________________________________________ 11. Let’s go to the school cafeteria. (about) _________________________________________________________________ 12. I couldn’t do the test because it was difficult. Because of _________________________________________________________ 13. Although he got up early, he was late for the first train. In spite of _________________________________________________________ 14. Although my friend doesn’t have enough money, she wants to buy that new car. Despite ___________________________________________________________ 15. We arrived late because of the bad traffic. Because ____________________________________________________________ 16. I enjoyed the film although the story was silly. In spite of ______________________________________________________________ 17. He didn't arrive until 9 o'clock although he promised that he wouldn't be late. (in spite of) Despite ______________________________________________________________ 18. I didn't listen to Western music some years ago. (used to) _____________________________________________________________________ 19. My mum was a chef in Cham restaurant, but now she is retired. (used to) _____________________________________________________________________ 20. There was a market here in 2003. (used to) _____________________________________________________________________ 21. The new restaurant looks good. It seems to have few customers. (however) ________________________________________________________________ ? 22. They didn't know how to drive a car, but now they can drive well. (used to) _____________________________________________________________________ 23. We planned to visit Petronas in the afternoon. We could not afford the fee. (however) _____________________________________________________________________ 24. Mary was sick. She didn’t leave the meeting until it ended. (despite) _____________________________________________________________________ 25. There were less vehicles on the roads in the past. (using “used to”) There________________________________________________________________

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