What is the potential energy of a 3kilogram-ball that is on the ground .

Asimply means that over time there was some sort of change.

Could someone . i have tried to solve myself but my calculation is off

In a heat engine if 1000 j of heat enters the system the piston does 500 j of work, what is the final internal energy of the system if the initial energy was 2000 j? 1. write the equation 2.list out your known variables 3.plug the numbers into the equations 4.solve 5.write your solution statement that includes initial energy and final