Cân bằng các pt sau : 1) Cu($NO_{3}$) $_{2}$ --> CuO + $NO_{2}$ + $O_{2}$ 2) $AgNO_{3}$ ---> Ag + $NO_{2}$ + $O_{2}$ 3) $ $Al(NO3$)_{3}$ --> Al2O3 +NO2 + O2 4) Al(OH)3 --> Al2O3 + H2O 5) Fe(OH)2 + O2 --> Fe2O3 + H2O Hỏi cho vui :3

giúp em bài 3 vs ạ cảm ơn mn ạ

A= 42/14.20 + 42/20.26 +....+ 42/80.86

hộ em bài này vs ạ e phải nộp gấp

Câu 7 tại sao hổ đó là trạng từ v ạ

X Bài toán 7: Tìm x biết: a) 126 - (x + 32) = 80 c) (x - 5) / 3 + 3 = 24 e) 23 + x / 2 = 37 b) (127 - x) - 15 = 72 d) (x - 4) / 3 - 2 = 100 f) (x - 52) - 62 = 32

II. Choose the best answer. 1. Mary's mother ____________ her to sing when she was five. A. teaches B. teach C. has taught D. taught 2. He ____________ newspapers for ten years. A. is selling B. sells C. has sold D. has been sold 3. There ______ fewer people and vehicles on the roads. A. used to B. used to be C. use to D. use to be 4. _____________ getting up early, I still missed the bus. A. Despite of B. Although C. In spite of D. Because of 5. ____________ have you lived in this town? A. How much B. How many C. How far D. How long 6. They____________ a holiday for ten years. A. haven't had B. didn't had C. don't have. D. aren't having 7. There ______ a bus station on the roads. A. used to B. used to be C. use to D. use to be 8. _____________ getting up early, I still missed the bus. A. Despite of B. Although C. In spite of D. However 9. She ____________ blood twenty times so far A. donates B. has donated C. is donating D. to donate

câu 3 ạ,cần gấppppp đang thi mà ko biết

Giúp mk vs ạ. Mk cần gấp ạ. Thanks các bạn nhiều

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