Answer
$v_{y}=-171\ m/s.$
Work Step by Step
We use the discussion of part (a).
We have found $ v_{0}=202m/s$, $\theta=-37^{o}$, and we are given that $t=5.00s$.
Eq. 4-23 gives the $v_{y}$ component of the velocity (just before impact)
$v_{y}=v_{0}\sin\theta_{0}-gt$
$=(202m/s)\sin(-37.0^{o})-(9.80m/\mathrm{s}^{2})(5.00s)$
$=-171m/s.$
