The Moon Has a Mass of 7 $\times$ 10²² kg and a Mean Radius of 1

Multiple Choice

The Moon has a mass of 7.35 $\times$ 10²² kg and a mean radius of 1.74 $\times$ 10⁶ m. The velocity required by the Apollo landing capsule to escape from the gravitational attraction of the Moon is

A) 2.40 km/s.
B) 1.70 km/s.
C) 1.45 $\times$ 10³ m/s.
D) unknown; we cannot answer this problem without knowing the mass of the orbiter.