#### Answer

$4|t|$

#### Work Step by Step

Using $\sqrt{x^2}=|x|$, the given expression, $
\sqrt{16t^2}
,$ simplifies to
\begin{array}{l}
\sqrt{(4t)^2}
\\\\=
|4t|
\\\\=
4|t|
.\end{array}
Note: We have to put the variable in absolute value bars since it is being raised to an odd power.