Explanation:
In our Solar System, a planet and its moon orbit each other due to two key forces: gravity and inertia. Gravity is the force that pulls two objects together, while inertia is the tendency of an object to stay in motion. In the context of a planet and its moon orbiting each other, gravity pulls the planet and moon towards each other, while inertia keeps them in a continuous orbit. A model of this would look like two circles, one larger than the other, with arrows pointing towards the center of the larger circle from both circles. This illustrates that the planet and its moon are being pulled towards each other by gravity, while inertia keeps them in continuous motion.