Answer
33.2 m
Work Step by Step
Let's apply the equation $S=ut$ in the horizontal direction to find the flight time of the rocket until it passes the wall.
$\rightarrow S=ut$ ; Let's plug known values into this equation.
$27\space m=75\space m/s\times cos60^{\circ}t$
$t=0.72\space s$
Let's apply the equation $S=ut+\frac{1}{2}at^{2}$ in the Vertical direction to find the height of the ball when it passes the wall
$\uparrow S=ut+\frac{1}{2}at^{2}$ ; Let's plug known values into this equation.
$S=75\space m/s\times sin60^{\circ}\times0.72\space s+\frac{1}{2}(-9.8\space m/s^{2})\times (0.72\space s)^{2}=44.2\space m$
Clearance = 44.2 m - 11 m = 33.2 m
