Answer:
Half as large.
Explanation:
Using Newton's law of universal gravitation, if the mass of the planet is M and of the Moons 1 and 2 is m, them the force exerted by the planet on them will be:
[tex]F_1=\frac{GMm}{r}[/tex]
[tex]F_2=\frac{GMm}{2r}[/tex]
Which clearly shows that the force that the planet exerts on the Moon 2 is half the force it exerts on the Moon 1.