An undiscovered planet, many lightyears from Earth, has one moon in a periodic orbit. This moon takes 1.655 x 10 seconds (about 19 days) on average to complete one nearly circular revolution around the unnamed planet. If the distance from the center Macmillan Learning of the moon to the surface of the planet is 275.0 x 10 m and the planet has a radius of 3.30 x 10 m, calculate the moon's radial acceleration ac . ac m/$2