Answer:
34.64 ft
Step-by-step explanation:
Distance from the building = 20 ft
Angle of inclination = π/3 radians
The tangent of the angle of inclination must equal the height of the building divided by the distance of the observer from the building:
[tex]tan( \pi/3) = \frac{h}{20} \\h = 20*1.73205\\h=34.64\ ft[/tex]
The building is 34.64 ft tall