Solving Orbital Angle Problem: Worked Examples & Tips for 9a, 9b, and 9c

[diovan]

The problem is stated here:

http://i56.tinypic.com/iderfc.jpg

I have included my work until the point I got stuck on.
I have worked out problem 9b) but can't figure out how to solve 9a) and 9c)
Thank you for any help.

 

[collinsmark]

The problem is stated here:

http://i56.tinypic.com/iderfc.jpg

I have included my work until the point I got stuck on.
I have worked out problem 9b) but can't figure out how to solve 9a) and 9c)
Thank you for any help.

For part 9a), calculate the orbital period of Mars. Divide 300 days by the orbital period. That number represents the fraction of the orbital period that the Pathfinder was on its trajectory. Convert that fraction to radians by multiplying by 2π.
(Think about it this way. Hypothetically, if it took Pathfinder exactly 1 orbital period (of Mars) to arrive, Mars would have traveled one complete circle, or 2π radians. Of course, it really takes Pathfinder less than 1 orbital period to arrive, and that's where the fraction comes in.) This approximation assumes that Mars travels in a circular orbit however. If you wanted to be more accurate and use Mars' elliptical orbit, more information needs to be given in the problem statement.