Avolleyball serve was in the air for 2.2 seconds before it landed untouched in the far corner of the
opponent’s court. what was the maximum height of the serve?

Given that air resistance is negative.
Hence the values are: 2.2 s G = 9.8 m/s2
Solution
Velocity = vf-vi = 0 – vi = -vi
V = 9.8m/s2 x 2.2 s = 21.56 m/ s (cancel one s out)
Vi = 21.56 m/s  

Then (s) displacement is
S=v x t
Average velocity = (21.56 m/s + 0 / 2)
Average velocity = 10.78 m/s
Time = 2.2 s  

S = 10.78 m/s x 2.2 s (cancel s)
S = 23.716 m  

Therefore the ball was at 23.716 meters in the air.