8,2 x 3,45 =28,29

\(\text{57 x 23 + 57 x 143 - 57 x 60}\)

\(\text{= 57 x ( 23 + 143 - 60 )}\)

\(\text{= 57 x 106 }\)

\(\text{= 6042}\)

\(32.x^5=6^5\)

\(32.x^5=7776\)

\(x^5=7776\div32\)

\(x^5=243\)

\(x^5=3^5\)

\(x=3\)

b

a

C

B

- Đỏ , son

- Trắng ,bạch

- Xanh,điều lục,biếc

1-A

2-D

3-C

D

D