Answer
$\sqrt[7]{m^3}$ or $\left(\sqrt[7]{m}\right)^3$
Work Step by Step
Recall the rational exponent property (pg. 382):
$a^{\frac{m}{n}}=\sqrt[n]{a^m}=(\sqrt[n]{a})^m$
Applying this property to the given expression (with $m=3$, $n=7$, $a=m$), we get:
$\sqrt[7]{m^3}=(\sqrt[7]{m})^3$
