Apsychological condition that can lead to poor sleep is

How much work would be needed to raise the payload from the surface of the moon (i.e., x = r) to an altitude of 5r miles above the surface of the moon (i.e., x = 6r)?

Why cooking gas has a typical smell

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 ?