Answer:
The displacement is 
The distance is 
Explanation:
From the question we are told that
The height from which the ball is dropped is 
The height attained at the first bounce is 
The height attained at the second bounce is 
The height attained at the third bounce is 
Note : When calculating displacement we consider the direction of motion
Generally given that upward is positive the total displacement of the ball is mathematically represented as

Here the 0 show that there was no bounce back to the point where Billy released the ball

=> 
Generally the distance covered by the ball is mathematically represented as

The 2 shows that the ball traveled the height two times

=> 
The force of gravity on objects is proportional to the mass of each object.
(That's a big part of the reason why, when you eat more and your mass
increases, you weigh more.)
The forces of gravity between the Earth and the 6kg ball are 50% greater
than the forces of gravity between the Earth and the 4kg ball.
(The gravitational forces between the 4kg ball and the 6kg ball, or between
both bowling balls and you, are so small that they may be ignored.)
I'm not exactly sure but I'm thinking that it's the last one. Sorry if I'm wrong
It's b, because the more force an object it is given the harder it will be for it to slow down.