A Satellite Encircles Mars at a Distance Above Its Surface

Multiple Choice

A satellite encircles Mars at a distance above its surface equal to 3 times the radius of Mars. If gm is the acceleration due to gravity at the surface of Mars, what is the acceleration due to gravity at the
Location of the satellite?

A) gm/9
B) gm
C) 0
D) gm/16
E) gm/3