Answer
$y^{8}$
Work Step by Step
We are given the expression $(y^{-4})^{-2}$.
To simplify, we can use the power rule, which holds that $(a^{m})^{n}=a^{m\times n}$ (where a is a real number, and m and n are integers).
$(y^{-4})^{-2}=y^{-4\times-2}=y^{8}$