Mars orbits the Sun at a mean orbital radius of 228 Gm (1 GM =109 m) and has an orbital period of 687 d. Earth orbitsthe Sun at a mean orbital radius of 149.6 Gm.
a) The Earth-Sun line sweeps out an angle of360° during one Earth-year. Approximately what angle is sweptout by the Mars-Sun line during one Earth-year?
b) How frequently are Mars and the Sun in opposition (ondiametrically opposite sides of Earth)?