Vẽ mầm cười*O_O* NL:cho mình xin thêm 2 cái sừng trên đầu của mầm nữa nhó:)) https://hoidap247.com/thong-tin-ca-nhan/826628#

Giải giúp mik bài 1 và bài 2 ạ, mình cần gấp ạ🥰

Một tia sáng chiếu tới một gương phẳng nằm ngang với góc i=30độ. Nếu tia tới cố định, để có tia phản xạ nằm ngang thì phải quay gương 1 góc nhỏ nhất là A. 15 B. 30 C. 45 D. 75

viết bài văn nêu suy nghĩ của em về lòng hiếu thảo ( ko chép mang, copy , phải dài nha ) giúp mik vs Mik đg cần gấp

Một gen có 3000 nucleotit ,khối lượng phân tử của gen đó là: A.9×105 B.9×104 C.3×105 D.3×104 Giải chi tiết hộ mình với Cảm ơn trước nha

Xương hóa thạch của loài vượn cổ xuất hiện khoảng 6 triệu năm trước đây được tìm thấy ở đâu? A. Đông Phi, Tây Á, Bắc Á B. Đông Phi, Tây Á, Việt Nam C. Đông Phi, Việt Nam, Trung Quốc. D. Tây Á, Trung Á, Bắc Mĩ.

Cảm nhận vẻ đẹp muôn màu của ánh trăng trong bài ngắm trăng của Hồ Chí Minh

1. No one is better at English than Lan,_________? A. is she B. isn't she C. are they D. aren't they 2. There are a lot of people attending the wedding party, _______? A. are they B. are there C. aren't they D. aren't there 3. He seldom goes to the park,__________? A. doesn't he B. is he C. does he D. isn't he 4. Let's go for walk,__________? A. will we B. shall we C. don't you D. do you 5. I think he will come here,________? A. doesn't he B. won't he C. will he D. don't I 6. The film is boring, ________? A. is it B. are they C. isn't it D. aren't they 7. You are listening to music,_________? A. is you B. are you C. aren't you D. were you 8. He can speak English,__________? A. can he B. can't he C. can't him D. could he 9. You don't know her,__________? A. do you B. don't you C. are you D. aren't you 10 Nga speaks English very well,_________? A. does she B. doesn't she C. is she D. was she 11. John has bought a dictionary,__________? A. does he B. did he C. has he D. hasn't he 12. They met him at the party last night,__________? A. do they B. don't they C. did they D. didn't they 13. They are going to do the test tomorrow,__________? A. do they B. are they C. aren't they D. did they 14. I'm short,__________? A. am not I B. aren't you C. are you D. aren't I 15. No one is in this room now,__________? A. is one B. isn't one C. is he D. are they 16. Somebody has stolen your bag,________? A. have they B. haven't they C. has he D. hasn't he 17. James often goes swimming in the summer,_________? A. does he B. is he C. doesn't he D. didn't he 18. You aren't doing your homework________? A. are you B. have you C. aren't you D. do you 19. This ticket doesn't cost a lot,__________? A. do they B. does it C. is it D. isn't it 20. You don't love me anymore,__________? A. do I B. don't I C. do you D. don't you 21. Nobody knows the truth,__________? A. do they B. don't they C. does it D. doesn't it 22. Nam was playing football,__________? A. was Nam B. wasn't he C. was he D. didn't he 23. You'll be at home tonight,_________? A. will you B. won't you C. are you D. won't you be 24. David is talking to his friend,_________? A. is he B. isn't he C. is David D. isn't David 25. Don't leave here,__________? A. do you B. don't you C. will you D. shall we 26. She thinks they will come,__________? A. does she B. doesn't she C. won't they D. will they 27. There is nothing to eat,_________? A. isn't there B. aren't they C. are they D. is there 28. The children can read the story, __________? A. can't they B. can they C. they can D. they can't 29. My brother shouldn't do that_________? A. should he B. are he C. shouldn't he D. aren't he 30. Lan never goes out at night_________? A. doesn't she B. does she C. isn't she D. is she

0.25 mol sắt oxit chứa 7,5.10^23 nguyên tử sắt và oxi. Hãy tìm công thức sắt oxit. HELP ME

Giúp mik với mik đang cần gấp .