Red Elk throws a ball with a purely horizontal velocity from the roof of a building that is 21 m tall.  
The ball lands 17 m from the base of the building.
a) What time is the ball in the air?
b) What is the velocity of impact in terms of an angle and a magnitude?
c) What is the velocity and position of the ball at exactly 1.1 seconds from its release?
d) What is the velocity and position of the ball at an elevation of 10.0 m from the ground?