Giúp mình các câu này với ạ Help me, please!

viết thư điện tử kể về 1 thành viên trông gia đình

Oxit cao nhất của nguyên tố R có phân tử lượng bằng 80đvC. Xác định nguyên tố R

72 x 9 + 38 x 9 - 9 x 10 81 + 81 x 5 + 81 x 4

Trong chọn giống cây trồng, người ta đã sử dụng những phương pháp nào? Phương pháp nào được xem là cơ bản? Cho ví dụ minh họa kết quả của mỗi phương pháp đó.

Cho A=5.7.9.11+15.17.19.Hỏi A là số nguyên tố hay hợp số ? Vì sao mong anh chị giúp em

Lập bảng biến thiên và vẽ đồ thị hàm số sau: y=|-3x^2-6x+4|

I. Choose the best answer (3.0 pts) 1. In most French and Italian homes, meals are an important part of family life ......... in the UK, a lot of families do not eat together. A. and B. when C. but D. however 2. The man decided …... a big house after winning the lottery. A. sell B. to buy C. selling D. buying 3. Her parents are proud ...… her studying at school.. A. of B. with C. for D. from 4. …....... is a machine that cooks food very quickly. A. cooker B. pan C. fridge D. microwave 5. He spent many hours ..… that work. A. finishing B. to finish C. finishes D. finished 6. He spent many hours … that work. A. finishing B. to finish C. finishes D. finished 7. Would you like some orange juice? - … A. Yes, I like. B. No, I don’t. C. Yes, please. D. No, I needn’t. 8. Last Sunday I was tired, so I … up until midday. A. wasn’t get B. don’t get C. didn’t get D. not get 9. Joseph Conrad was Polish but he … English very well. A. brought B. spoke C. spent D. saw 10. Tom was a doctor and help Fleming to go to university and study medicine. A B C D (Find out the mistake and circle A, B, C or D) 11. Paris Hilton is the eldest … four children. A. with B. of C. for D. from 12. How was your weekend? - … A. Yes, I’d love too. B. It’s OK. C. We were OK. D. It was OK, thanks. 13. We had a barbecue ………….the garden. a. in b. at c. on d. of 14. There are 300 million cubes ………………the world. a. of b. from c. in d. over 15. She didn’t get a ……………..when she left school. a. work b. job c. duty d. task 16. I went to the cinema, but the film was really ……………… a. good b. interesting c. boring d. excellent 17. Lászlo Bíro was a great ………………….. a. invent b. invention c. invented d. inventor 18. We had lunch in a café, then we …………...shopping. a. go b. went c. going d. goes 19. Last night I …………….. out, I stayed in. a. not go b. didn’t go c. not went d. not going 20. A: “I went for lunch with some friends, but the food was terrible.” – B: “………..” a. Very good! b. What a disaster! c. Well done! d. Good job! 21. A: “How was your weekend? – B: “…………..” a. It was OK, thanks. b. I was tired. c. It’s good. d. Badly. 22. Lan is from Hungary. She is _____________. a. Japanese b. Czech c. Croatian d. Hungarian 23. My father _____________ some chocolate the day before yesterday. a. To buy b. buy c. bought d. buying 24. _____________ you make a phone call two days ago? a. Do b. Did c. Does d. Are 25. What is your mother's nationality? – She is Romanian. She comes from _____________. a. Slovakia b. Romania c. Spain d. Ukraine 26. My little sister _____________ a bad dream last night. a. Ate b. listened c. had d. got 27. Rosa Parks refused _________ up for a white person on the bus. a. to give b. standing c. to stand d. giving 28. They all decided _________his work and to fight _________ the rights of black American. a. to continue-for b. continued-for c. continue-of d. to continue-in 29. Eric got a _________ in a chemical laboratory. a. job b. work c. jobs d. works 30. They try __________ something new about her life. a. To learn b. learn c. learns d. learning 31. I don't think money is the _________ thing in life. a. More important b. importantest c. most important d. importanter

hãy cho biết ý nghĩ của cách viết sau:5C,6Na,3S

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