The fraction of energy that is lost is 25%, it depends how fast the ball was going until it lost 25% of its energy, the gravitational energy was transferred into the kinetic energy that helped the ball bounce back
Answer:

Explanation:
From the question we are told that:
Mass 
Drop distance 
Generally the equation for Spring Constant is mathematically given by



It would be A because it would make sense
Answer:
The acceleration is -9.8 m/s²
Explanation:
Hi there!!
When you throw a ball upward, there is a downward acceleration that makes the ball return to your hand. This acceleration is produced by gravity.
The average acceleration is calculated as the variation of the speed over time. In this case, we know the time and the initial and final speed. Then:
acceleration = final speed - initial speed/ elapsed time
acceleration = -4.3 m/s - 4.3 m/s / 0.88 s
acceleration = -9.8 m/s²
I believe the correct answer is C all the other options seem funny to me