Kinematics

The path of the ball is a vector and we break it into its different
components.

(a) We break up the initial velocity of the ball:
<img src="http://physweb.bgu.ac.il/cgi-bin/mimetex.cgi? v_{0x}  =  (25.3\frac{m}{s})cos(42.0^{o})=18.8\frac{m}{s}\\ v_{0y}  =  (25.3\frac{m}{s})sin(42.0^{o})=16.9\frac{m}{s}">
The ball is in the air for a time t=x/v_{x}=(21.8m)/(18.8m/s)=1.16s
before it hits the wall.

(b)y=-gt^{2}/2+v_{oy}t=-(4.91m/s^{2})(1.16s)^{2}+(16.9m/s)(1.16s)=13.0m.

(c)v_{x}=v_{0x}=18.8m/s,\: v_{y}=-gt+v_{oy}=-(9.80m/s^{2})(1.16s)+(16.9m/s)=5.53m/s.

(d) Since v_{y}>0, the ball is still going up and has not passed
the highest point yet.