Solve each problem involving triangles. See Examples 1–4. Height of a Buildin...

Solve each problem involving triangles. See Examples 1–4.

Height of a Building From a window 30.0 ft above the street, the angle of elevation to the top of the building across the street is 50.0° and the angle of depression to the base of this building is 20.0°. Find the height of the building across the street.