Answer:
The factor is 0.60
Explanation:
we know that
The expression that model this situation is a exponential equation of the form

where
h is the height of the ball in feet
x is the number of bounces
a is the initial height
b is the factor
we have

so

Verify
First bounce
For x=1
---> is ok
Second bounce
For x=2
---> is ok
Third bounce
For x=3
---> is ok
therefore
The factor is 0.60