Answer: it should be when you’re going down the highest hill
Step-by-step explanation:
The reasoning behind this is; your potential energy is the energy you have when you’re, let’s say at the peak of the roller coaster, your potential energy (energy that is not yet in use but COULD be) determines the amount of kinetic energy possible, so you’re at the highest peak, you have the most potential energy therefore giving you the most kinetic energy! Hope this helps a bit