What does it mean for a quantity to be conserved? Why are conserved physical quantities useful to physicists? 
Give an example which illustrates the difference between three kinds of energy and the transformation of energy from one kind to another.   Your example may include some of the following kinetic, thermal, gravitational potential, and spring potential energy.
In your example explain the difference between Energy, Work, and Power.
Be sure to provide substantive responses to at least two of your classmates. For instance a response referencing some specific point in the post to which you are responding is a substantive response. Another example of a substantive post is one which prompts your classmate to address some missed point of the discussion. As always responses such as, “Good Job,” and “I agree,” are considered non substantive and earn no points.