Answer
The angle of elevation to the top of the wall is $41^{\circ}$.
Work Step by Step
Refer to the attachment for variables:
1. Use the sine law to find $\angle C$
$\frac{sinC}{3} = \frac{sin90}{4}$
$sinC = \frac{3sin90}{4}$
$sinC = \frac{3}{4}$
$C = sin^{-1}(\frac{3}{4})$
$C = 48.590...^{\circ}$
2. Find $\angle α$
$\angle α = 180 - (48.590... + 90)$
$\angle α = 180 - 138.590...$
$\angle α = 41.409...^{\circ}$
$\angle α \approx 41^{\circ}$
