Given a scientific question and its correct answer, generate supporting facts for the answer. This supporting fact can be an explanation for the answer to the given question.

[EX Q]: Question: What is the point on the ground that is located directly above where underground rocks fracture (or the "focus" point)? Answer: epicenter
[EX A]: The focus is where the rocks rupture. The epicenter is the point on the ground directly above the focus.

[EX Q]: Question: Name the process of removing wastes from the body. Answer: excretion
[EX A]: Excretion is the process of removing wastes from the body.

[EX Q]: Question: Define motion. Answer: change of position
[EX A]:
Motion is defined as a change of position.