In both cases shown at right, an astronaut is a distance x from a moon. The two cases are identical except that in Case A there is a large planet directly between the astronaut and the moon.

a) Is the gravitational force on the astronaut by the moon greater in Case
A, greater in Case B, or the same in both cases? Explain your reasoning.
b) In which case will the astronaut have greater acceleration? Explain your reasoning.