Answer:
magnifying glass
Explanation:
makes objects bigger and smaller / used in science
Friction is the force you get when you (for example) Rub something with another, it's a force that may generate heat and even some resistance. Another example is rubbing your hands together, they get hot, therefore friction is working, without friction you wouldn't be able to stop moving.
c) only from warmer areas to colder areas.
The second principle of thermodynamics states that heat can only flow from a hotter body to a cooler one. Specifically, Clausius statement says that is not possible for heat to move by itself from a lower temperature body to a higher temperature body.