Answer:
top of the highest hill
Step-by-step explanation:
The potential energy of an object is given by
![U=mgh](https://img.qammunity.org/2021/formulas/physics/middle-school/g40n03woz39gur7y23rmsdjh1j6xykiiwr.png)
where,
m = Mass of the object
g = Acceleration due to gravity
h = Perpendicular distance from the ground.
It can be seen that the potential energy is proportional to height
![U\propto h](https://img.qammunity.org/2021/formulas/physics/high-school/oadutasjb1xdv3yvdcugkpj6t4tnuetakc.png)
Here, the car will have maximum potential energy when it is at the maximum distance from the ground.
Hence, the car will be at the top of the highest hill