As of 2017, the tallest roller coaster in the world is the Kingda Ka, located at Six Flags Great Adventure in Jackson, New Jersey. It stands 139 meters tall and, at one point, the cars drop 127 meters! Roller coasters are a great way to investigate energy. Look at the diagram of a roller coaster below, and answer the following questions. At what point on the track does the car have the greatest potential energy?