Answer
$\frac{n^{3}}{m^{3}}$
Work Step by Step
When a fraction is raised to a power, we distribute the power to everything in the numerator and denominator of the fraction. Thus, we obtain:
$ (\frac{m}{n})^{-3}=\frac{m^{-3}}{n^{-3}}=\frac{n^{3}}{m^{3}}$
