<h2>You input potential (stored) energy into the rubber band system when you stretched the rubber band back. Because it is an elastic system, this kind of potential energy is specifically called elastic potential energy.</h2><h2>Hope it helps..</h2>
Heat engines are less than 100% efficient because absolute zero cannot be reached
Atomic mass= number of protons + number of neutrons

hope this helps
Formula for distance is d=st
so for speed is s=d/t
48 km per hour