Bài 69:Cho a gam hỗn hợp CuO và Fe2O3 tác dụng đủ với 100 ml dd HCl 1 M thu được 2 muối có tỉ lệ mol 1:1.Giá trị của a là ?

|x-3,5|+|y-1,3|=0 |x-3,4|+|2,6-x|=0 giúp mình ạ

. Complete each of the following sentences by circling the best option A, B, C or D. (6,0 pts) 1. I ____________ a letter from my old friend last week. A. sent B. gave C. received D. took 2. When were you born? – I was born ____________ November 1997. A. in B. on C. at D. during 3. Don’t come in. Pleased wait ____________ for your turn. A. inside B. downstairs C. outside D. upstairs 4. Our friends ____________ meet us at the airport tonight. A. are B. are going to C. go to D. will be to 5. The children ____________ are going to plant trees and flowers in the school garden and water them every afternoon after school. A. themselves B. ourselves C. herself D. themself 6. I know you worked really ____________ this semester. A. hardly B. good C. bad D. hard 7. The sun ____________ in the east. A. rise B. set C. sets D. rises 8. Martina has been a professional tennis player ____________ 1994. A. since B. for C. on D. in 9. ____________ have you known Jane? – For three years. A. What B. How many C. How long D. How far 10. The water wasn’t ____________ in. A. clear enough to swim B. enough clear to swim C. clear enough for swimming D. enough clear for swimming 11. I really love ____________ shoes. It’s relaxing! A. clean B. cleans C. to clean D. cleaning 12. We got ____________ in the woods. A. lot B. lost C. loss D. lose 13. His parents are always proud ____________ him because he always studies well. A. about B. on C. of D. with 14. Last week, her ____________ was out of order and Mrs. Quyen had to wash her family’s clothes with her hands. A. shower B. washing machine C. kitchen sink D. iron 15. Mr. Brown is 50 years old; Mrs. Brown is 50 years old. Mr. Brown is ____________ Mrs. Brown. A. same age B. same age as C. the same age as D. different from 16. My grandfather used ____________ us to the zoo when he was alive. A. take B. took C. taking D. to take 17. You ____________ to eat more, you are far too thin. A. ought B. should C. must D. can 18. Nam’s father ____________ him how to ride a bike six years ago. A. teach B. teaches C. has taught D. taught

moi nguoi giup minh voi minh se tich 5sao

nhờ mng giải giúp em bài này với ạ, em cảm ơn

Khí Clo có 2 đồng vị là $\frac{35}{17}$Cl và $\frac{37}{17}$Cl. Nguyên tử khối trung bình của Cl là 35,54. Tính thành phần phần trăm số nguyên tử của mỗi đồng vị.

Tam giác ABC vuông tại A, AB= 6, AC= 8 Tính: $|\overrightarrow{CA} + \overrightarrow{CB}|$

Mình cần gấp ngay tối nay nhé. Ko chép mạng và đúng kiểu đoạn văn. Mình sẽ vote 5* và ctlhn

lười quá ai giúp đi 😅😅😅😅😅😅

Tìm giá trị lớn nhất của hàm số : y= sin^2x - 4sinx + 8