Hand written solution required

A negative electron of rest mass 9.11 x 10" kg is moving forward at 95% the speed of light. It collides with a positive alpha particle of rest mass 6.68 x 102kg which is moving in the reverse direction at 200 m/s. The two particles experience an inelastic collision as they are electrically attracted to one another and the new combined particle is a Helium atom. Determine the final velocity of the Helium atom. Then determine the heat loss in Joules (J) and also in electron-volts (eV). 200 m/s ??? 0.95 c +2 no e p* no e p* a - He a - He no no p* p*