Answer:D
Explanation: Hope this helps!
Acceleration can be defined as the change of speed in an instant of time, that is

Here,
Final velocity
Initial velocity
Change in time
From this expression we will calculate the requested values replacing the variables in each of the given terms
PART A) The values under this condition are:



Replacing,


PART B ) The values under this condition are:



Replacing,


Therefore the acceleration in the second time interval is
PART C) The values under this condition are:



Replacing,


OPTIONS :
A.) the force that the ball exerts on the wall
B.) the frictional force between the wall and the ball
C.) the acceleration of the ball as it approaches the wall
D.) the normal force that the wall exerts on the ball
Answer: D.) the normal force that the wall exerts on the ball
Explanation: The normal force acting on an object can be explained as a force experienced by an object when it comes in contact with a flat surface. The normal force acts perpendicular to the surface of contact.
In the scenario described above, Erica's tennis ball experiences an opposite reaction after hitting the wall.This is in relation to Newton's 3rd law of motion, which states that, For every action, there is an equal and opposite reaction.
The reaction force in this case is the normal force exerted on the ball by the wall perpendicular to the surface of contact.
1.7 x 10^2 N
or 166 N
First you find the vertical component of the weight, which is 9.8*40, (g*m), which is 392 N. You then find the angle between that and the slope, which is 90-25, which is 65. You then multiply the vertical weight by cos(65), to find the component of that that is parallel to the slope. You get 165.666 N