Answer: 292.95 J
Explanation:
change in internal energy= Heat transfer - work done
ΔU =Q -PΔV
Here, Q = 0 as there is no heat transfer.
P =2.00 atm = 2.00 × 101235 Pa = 202470 Pa
ΔV = final volume - initial volume = 0.8 V -V = -0.2 V
where V is the initial volume.
Volume of a spherical ball, 
r = d/2 = 23.9 cm / 2 = 0.12 m


Hence, internal energy would change by 292.95 J.
Answer:
the normal force that the wall exerts on the ball
Explanation:
As Newton's third law states:
"when an object A exerts a force on object B, then object B exerts an equal and opposite force on object A".
If we apply this law to this problem, we can identify the ball as object A, and the wall as object B. As the ball hits the wall, the ball exerts a force on the wall (toward the direction of motion of the ball), so the wall exerts an equal and opposite force on the ball (in the opposite direction). This force is the normal force of the wall, and it is responsible for pushing the ball back towards Erica.
It is Continental polar ( only if this is for apex)