Answer
No, $(\frac{2}{3})^{-2}$ is not equal to $3^{4}$.
Yes, there is difference between $(-5)^{4}$ and $-5^{4}$.
Work Step by Step
A.
$(\frac{2}{3})^{-2}$
= $(\frac{3}{2})^{2}$
= $\frac{3\times3}{2\times2}$
= $\frac{9}{4}$ which $\ne$ $\frac{3}{4}$
B.
Here,
$(-5)^{4}$ = $(-5)\times(-5)\times(-5)\times(-5)$ = 625
$-5^{4}$ = -($5\times5\times5\times5$) = -625
and 625 $\ne$ -625, so there is difference between $(-5)^{4}$ and$-5^{4}$.
