Select all of the following events in which a physical change occurs a. chocolate syrup dissolves in warm milk

b. toast is lightly charred in a toaster

c. sugar is heated until it turns into a brown caramel substance

I think it is case A and case B because they change physically, so the first from solid chocolate to liquid. This can be explained as a physical change.

only about ten percent of the energy at one trophic level is passed on to organisms at the next trophic level. the remainder of the energy is used in life processes or lost as heat.