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9 An undiscovered planet, many lightyears from Earth, has one moon in a periodic orbit. This moon takes 1.655 x 106 seconds i (about 19 days) on average to complete one nearly circular revolution around the unnamed planet. If the distance from the center i of the moon to the surface of the planet 1s 235 0 x 106 m and the planet has a radius of 3 30 x 106 m, calculate the moon' 5 radial acceleration ac. mallInn