#### Answer

$-4$

#### Work Step by Step

RECALL:
(i) $\sqrt[n]{a^n} = a$ when $n$ is odd
(ii) $\sqrt[n]{a^n} = |a|$ when $n$ is even
Write the number inside the radical sign as a fourth power, and then use rule (ii) to obtain:
$=-\sqrt[4]{4^4}
\\=-4$