A spherical planet is discovered by astronomers orbiting a star which has the same mass as our Sun. The orbital period of the planet is 2.55 Earth years, it has a radius of 7500 km, an average density of 5200. kg/m3 ,and orbits in a circular path. Assume that only the star has an appreciable gravitational affect on the planet.
a. How far from the star (in AU) does the planet orbit?