A space probe is launched from Earth headed for deep space. At a distance of 10,000 miles from Earth's center, the gravitational force on it is 600lb, what is the size of the force when it is at each of the following distances from the Earths surface?
A20,000 miles
B30,000 miles
C100,000 miles
A20,000 miles
B30,000 miles
C100,000 miles