Compute all parts of following problem given below:
Problem: Marooned on a desert island and with a lot of time on your hands, you decide to disassemble your glasses to make a crude telescope with which you can scan the horizon for rescuers. Luckily you're farsighted, and as for most people your two eyes have somewhat different lens prescriptions. Your left eye uses a lens of power +4.5 D, and your right eye's lens is +3.0 D.
Part A: Which lens should he use to view object and for which for eye piece?
Part B: What will be your magnification on your telescope?
Part C: Approximately how far apart should the two lenses be when you focus on distant objects?
I want you to clarify the physics in this above problem.