1. The problem statement, all variables and given/known data Attached. A and D are circular. Find the orbit with largest angular momentum, largest total energy, and largest maximum speed. 2. Relevant equations E is proportional to -1/a (elliptical; a is semimajor axis) U is proportional to -1/r K is proportional to 1/r (circular only) dA/dt is proportional to L T^2 is proportional to a^3 3. The attempt at a solution I want to see somebody work it out the 'right' way, since I'm more or less fooling around with no idea what I'm doing. (a) I have (not sure) that L is proportional to sqrt(r) for circular orbits, so A is higher than D. Since C and B are going slower than A at aphelion, A beats them too. So the answer is A? (b) is A since it has the largest semimajor axis. (c) No idea; I know it's not D, but then I'm not sure on the rest. A has highest energy, B has much less but makes a much closer approach.