B

B.
 \(=\left(3^4\right)^3:3^5=3^{12}:3^5=3^7\)

cÂu B 

A nha

nhớ tick cho mik <3

5B

6A

Câu 5 : B

Câu 6: D

b: \(\Leftrightarrow x+\dfrac{2}{5}=\dfrac{2}{3}\)

hay \(x=\dfrac{1}{15}\)

a) \(\Rightarrow\left|\dfrac{3}{4}+x\right|=0\Rightarrow\dfrac{3}{4}+x=0\Rightarrow x=-\dfrac{3}{4}\)

b) \(\Rightarrow x+0,4=\dfrac{4}{9}:\dfrac{2}{3}=\dfrac{2}{3}\Rightarrow x=\dfrac{2}{3}-0,4=\dfrac{4}{15}\)

A

A

Câu A

\(=\dfrac{101}{2}\left(4+\dfrac{5}{3}-2-\dfrac{5}{3}\right)=\dfrac{101}{2}\cdot2=101\)

Câu 4:B

Câu 5:A

4b vì góc tới bằng góc phản xạ nên lấy 80/2=40

1. illegal

2. traffic jam

3. seatbelt

4. safely

5. railway station

6. safety

7. traffic signs

8. helicopter

9. tricycle

10. boat