The mass of a particle is frequently expressed in units of MeVie. You cle is frequently expressed in units of Meyle You can do this for the cases above by just converting Joules to MeV to get the energy in Mey. The mass is just stated as that over e-squared rather than actually doing the division by (3x10'). a) Rest mass for an electron in MeV/c. b) Find the relativistic mass of the muon from the previous section in units of MeVic 4) A photon is a massless particle that has energy and momentum. a) Using the relations above, what is the relation between total energy and momentum for the photon