Answer
$(3^2)^4=3^{8}$, see explanations.
Work Step by Step
The Power Rule (Powers to Powers) states that when an exponential expression, such as $3^2$, is raised to a power, such as $(3^2)^4$, multiply the exponents; in this case, $2\times4=8$. Place the product of the exponents on the base and remove the parentheses; in this case, $(3^2)^4=3^{8}$