Astronomy Homework help with Prometheus and Pandora.?

[dana]

These two moons orbit Saturn at 139350 and 141700 kilometers.
1.) Using Newton's version of Kepler's third law, find orbital period of Prometheus and Pandora. (in hours)
2.) Consider the two in a race around Saturn: In one Prometheus orbit, how far behind is Pandora (in units of time)?
3.) In how many Prometheus orbits will Pandora have fallen behind by one of its own orbital periods? Convert this number of periods back into units of time. This is how often the satellites pass by each other.(in days)