Pour the water from part B into one of the large containers. Pour the vinegar into the other large container. Observe the two combinations. Pick up each container one at a time and place your palm on the bottom to see whether you can feel a little difference in temperature. Record what you see and feel

answer would be letter choice (a),   a ball resting on a shelf. would be another example of potential energy   >   stored energy > not moving.

a ball spinning on a finger   >   kinetic energy > moving energy

a ball rolling on the ground   >   kinetic energy   > moving energy

a   ball flying through the air   > kinetic energy   >   moving energy

hope that                                         : )

there are no contact forces mentioned on the list of choices that you've provided.