A planet exerts a gravitational force of magnitude on a star. If the planet were 4 times closer to the star (that is, if the distance between the star and the planet were 1/4 what it is now), what...

A planet exerts a gravitational force of magnitude on a star. If the planet were 4 times closer to the star (that is, if the distance between the star and the planet were 1/4 what it is now), what would be the magnitude of the force on the

star due to the planet?