Five planets orbit identical stars. The planet names, mass, and semi-major axis are as follows: Abydos: 0.5 Earth-mass planet with semi-major axis 20 AU Pern: 1 Earth-mass planet with semi-major axis 1 AU Arrakis: 45 Earth-mass planet with semi-major axis 0.3 AU Magrathea: 10 Earth-mass planet with semi-major axis 1 AU Trantor: 1 Earth-mass planet with semi-major axis 11 AU Using Kepler's third law, decide which answer lists the planets based on their orbital periods from longest to shortest.