Answer
$\frac{1}{k^{4}}$
Work Step by Step
According to the product rule for exponents, $a^{m}\times a^{n}=a^{m+n}$ (where $m$ and $n$ are integers and $a$ is a real number).
Therefore, $k^{-5}k^{-3}k^{4}=k^{-5+(-3)+4}=k^{-4}$.
According to the definition of negative exponents, $a^{-n}=\frac{1}{a^{n}}$ (where $a\ne0$).
Therefore, $k^{-4}=\frac{1}{k^{4}}$.
