An incident x-ray photon is scattered from a free electron

Question

Solve the following problem given below:

Problem: An incident x-ray photon is scattered from a free electron that is initially at rest. The photon is scattered straight back at an angle of 180? from its initial direction. The wavelength of the scattered photon is 8.60 x 10² nm.

Part I: What is the wavelength of the incident photon?

Part II: What is the magnitude of the momentum of the electron after the collision?

Part III: What is the kinetic energy of the electron after the collision?

Please use as much detail as possible in solution.