NASA Satellites Stay Up Because

Multiple Choice

NASA satellites stay up because

A) they are away from Earth's gravity and thus do not get pulled down toward Earth.
B) they are moving so fast that they are able to "fall" around Earth.
C) there is no air resistance in outer space and thus no downward force on an orbiting satellite.
D) centrifugal force pulls outward on them.
E) their rocket engines hold them above Earth's surface.