Answer
$\frac{256}{t^{4}}$
Work Step by Step
According to the definition of negative exponents, $a^{-n}=\frac{1}{a^{n}}$ (where $a\ne0$).
Therefore, $(\frac{t}{4})^{-4}=\frac{1}{(\frac{t}{4})^{4}}=(\frac{4}{t})^{4}=\frac{4^{4}}{t^{4}}=\frac{256}{t^{4}}$.