2. Mass as a Measure of Energy (1 mark) Beta decay involves the decay of a neutron into a proton, an electron and an electron antineutrino, De (with negligible rest mass) according to: nopte+v. The decay products are measured to have a total kinetic energy of 0.78110.005 MeV. Show that this observation is consistent with the excess energy predicted by the Einstein mass-energy relationship