Answer
$15.1^{\circ}$
Work Step by Step
Since, $\sin \theta= \dfrac{height}{hypotenuse}$
We have the angle of elevation for the ramp $\theta= 90^{\circ}$
We can use the sine of the triangle to solve for the angle.
$\sin \theta= \dfrac{6}{23}$
or, $\theta=\sin^{-1} \dfrac{6}{23}$
or, $\theta=15.1^{\circ}$
