The cotton gin is a machine that easily separates cotton fibers from their seeds.
Answer:
Hand washing has external health benefits, helping prevent the spread of communicable diseases. If a program were somehow devised so that people received a small reward every time they washed their hands, we would expect the frequency of hand washing to increase.
Explanation: People who are given something (A reward of some sort) are proven to do something more, (in this case washing their hands more), or better then they would do without a source of motivation.
Answer:
An ellipse is a specific curve: the closed path taken by a point that moves in such a way that the sum of its distance from two fixed points (called foci) is constant. For a satellite orbiting a planet, one focus is at the center of planet; the other focus could be internal or external to the planet. It is called an ellipse.
Explanation:
