1. What does your father do in the afternoon?

2. Do you like reading comic book?

3. What do your brother and sister do in their free time?

4. My father and my mother are watching TV in the living room.

= 9^2x10 : 9⁵⁺⁶⁺⁷

= 9²⁰ : 9¹⁸

= 9²

X = 150

X-47 = 115

X= 115 +47

X =162

a)Fe + 2HCl -> FeCl2 + H2

b) n Fe = n H2 = 0,15 mol

mFe = 0,15 x 56 = 8,4

c) cM = 0,3/0,05 = 6 M

Số khẩu trang ban đầu là:

12:3x5=20 

(36x11x2x17x3)/(11x17x36x2) = 3

3^x x (1+3-9+27) = 594

3^x = 27

x =3

a, (S)Na2O, b, (S) MgCl2, c, (Đ) FeCl2, d, (S) ZnO, e, (Đ) N2O