A student claps once when standing 100 m away from a large wall. The speed of sound in air is 330 m/s. How long after clapping does the student hear an echo?

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