Answer
Please see the work below.
Work Step by Step
We know that
$K_U=K_{\circ}+U_{\circ}$
$\implies (\frac{1}{2})mv^2+0.0=(\frac{1}{2})mv_{\circ}^2+mgh$
$\frac{1}{2}mv^2=\frac{1}{2}mv_{\circ}^2+mgh$
$\frac{1}{2}v^2=\frac{1}{2}v_{\circ}^2+gh$
$v^2=v_{\circ}^2+2gh$
$v=\sqrt{v_{\circ}^2+2gh}$
