What is the difference between elements and compounds? *

Imagine that you push on a large rock. at what point does your effort change the rock’s mechanical energy?

Which of the following are sources of revenue for media companies? a. direct sales to producers b.advertising and subscriptions c. online purchase d. capital investments

In a heat of an engine, if 700 j enters the system, and the piston does 400 j of work what is the final internal (thermal) energy of the system if the initial energy is 1,500 j