<u>Answer:</u>
Speed at which the ball leaves the launcher = 6.34 m/s
<u>Explanation:</u>
The readings of height above the floor reached by the ball = 2.32, 2.26 and 2.37
Mean value 
Initial height of launcher = 27 cm = 0.27 cm
So maximum height of projection = 2.317-0.27 = 2.047 meter
We have equation of motion,
, where u is the initial velocity, v is the final velocity, s is the displacement and a is the acceleration.
In this case we need to consider only vertical factors.
Vertical displacement = 2.047 m, acceleration = acceleration due to gravity =
, final velocity = 0 m/s, we need to calculate initial velocity.

So, speed at which the ball leaves the launcher = 6.34 m/s