#### Answer

60$^{\circ}$F

#### Work Step by Step

Since April is represented by $x=3$, we substitute $x=3$ in the equation to find the value of $t$:
$t=60-30\cos\frac{x\pi}{6}$
$t=60-30\cos\frac{3\pi}{6}$
$t=60-30\cos\frac{\pi}{2}$
$t=60-30(0)$
$t=60-0$
$t=60$
Therefore, the maximum afternoon temperature for the month of April is 60$^{\circ}$F.