So the planet is not unusual. A planet is discovered circling a nearby star just like the Sun. Its mass is determined to be kg and its distance from the star is km. We expect that for a star just like our sun, its planetary system would have formed just like ours. The mass and distance given in the problem are similar to Saturn or Jupiter, and we therefore would expect it to be a Jovian world as well.
Molecular oxygen weighs kg, while helium weighs kg.
The rule of thumb is that if the thermal velocity of a gas is less than six times the escape speed of the planet, the planet will retain the gas in its atmosphere, and therefore Mars can hold on to its oxygen even in summer. Helium, which is given in the problem as 8 times lighter than molecular oxygen, will have a thermal velocity which is 8 times faster and therefore will be able to escape Mar's gravitational grip. One suggestion is to add carbon dioxide to its atmosphere. Explain the effect carbon dioxide would initially have on Mars's temperature. To maintain the insulating atmosphere, Mars would either need active volcanism to replenish the greenhouse gases or would have to have artificially added on a regular basis.