A ball is projected to the top of a triangular building as shown in Fig. 1. The wall of the bulling

makes angle of a with horizontal line (Fig. 1). Find the initial projectile angle,, with respect to

the horizontal line in terms of angle a such that the ball strikes the top of the building. Find the

height of the building if a = 30.0° and the initial velocity is 20.0 m/s.

Fig. 1