Answer
$x^{25}y^{15}z^{15}$
Work Step by Step
Using laws of exponents, then,
\begin{array}{l}
\left( \dfrac{x^{-5}y^{-3}}{z^3} \right)^{-5}
\\\\=
\dfrac{x^{-5(-5)}y^{-3(-5)}}{z^{3(-5)}}
\\\\=
\dfrac{x^{25}y^{15}}{z^{-15}}
\\\\=
x^{25}y^{15}z^{15}
.\end{array}
