Answer
$\frac{5}{a^{4}}$
Work Step by Step
We are given the expression $5a^{-4}$.
In general, we know that $a^{-n}=\frac{1}{a^{n}}$ (where a is a nonzero real number and n is an integer).
Therefore, $5a^{-4}=5\times\frac{1}{a^{4}}=\frac{5}{a^{4}}$.
Since the 5 is not in parentheses with a, we evaluate the exponent with only $a$ as its base.