Answer
$1.38m$
Work Step by Step
We know that
$p=mv$
$\implies v=\frac{p}{m}$
$v=\frac{0.780}{0.150}=5.20\frac{m}{s}$
We also know that:
$y_{\circ}=\frac{v^2}{2g}$
We plug in the known values to obtain:
$y_{\circ}=\frac{(5.20)^2}{2(9.81)}$
$y_{\circ}=1.38m$