Answer
a. $111.96$ $ft/s$ or $76.34$ $miles/hr$
b. $82.42$ $ft/s$ or $56.2$ $miles/hr$
c. $x>18.82^{\circ}$
Work Step by Step
a.
$tan\theta=\frac{30}{x}$
$tan15=\frac{30}{x}$
$x=111.96$ $ft/s$ or $76.34$ $miles/hr$
b.
$tan\theta=\frac{30}{x}$
$tan(20)=\frac{30}{x}$
$x=82.42$ $ft/s$ or $56.2$ $miles/hr$
c.
$55+5$ $miles/hr \rightarrow 88$ $ft/s$
$tan\theta=\frac{30}{88}$
$\theta=18.82^{\circ}$
