Answer:
Potential energy is 
Explanation:
The potential energy depends on the mass, the acceleration of gravity g and the height at which the object or person is.
Potential energy 
In this case we would need to know the exact mass of the hiker in order to calculate the potential energy.
But we know the values of g and h


So, the potential energy

m is the mass of the hiker, wich is not in the description of the problem.
Answer:
<h2>18150 J</h2>
Explanation:
The kinetic energy of the car can be found by using the formula

m is the Mass
v is the velocity
From the question we have

We have the final answer as
<h3>18150 J</h3>
Hope this helps you
1 gallon has 0.133681 cubic feet