Answer
$\frac{1}{5^{6}}$
Work Step by Step
According to the quotient rule for exponents, $\frac{a^{m}}{a^{n}}=a^{m-n}$ (where $a\ne0$).
Therefore, $\frac{5^{-4}}{5^{2}}=5^{-4-2}=5^{-6}$.
Furthermore, the definition of negative exponents tells us that $a^{-n}=\frac{1}{a^{n}}$.
Therefore, $5^{-6}=\frac{1}{5^{6}}$.
