5. A photon of energy E strikes an electron at rest and undergoes pair production, producing a positron and an electron: photon + e * = e * + Positron + e * The two electrons and the positron move off with identical momenta in the direct ion of the init ial photon. Find the kinet ic energy of the three final particles and find the energy of the photon. How to do this? I seem to not get the right answer.