The answer is C- air resistance
<span>So we want to know why is a car racetrack built with a steep inward slope. When a car is moving on a circular path, it experiences a centrifugal force. This force is bigger as the car speed rises. So to counteract that force the steep inward slope is creating a force component towards the center of the circle that comes from the car's own weight so the car doesn't slide off the road. </span>
Answer:

Explanation:
Given data:
Mass of the man, 
Total mechanical energy, 
Height, 
Suppose there is no external force acting on the man. In this situation, the total mechanical energy (kinetic + potential) will remain steady.
Let the speed of the man at 2.6 m be <em>v</em>.
Thus,



