A particle a traveling along the positive x axis of frame S with speed 0.5c decays into two identical particles, a b b, both of which continue to travel on the x axis. (a) Given that ma = 2.5mb, find the speed of either b particle in the rest frame of particle a. (b) By making the necessary transformation on the result of part (a), find the velocities of the two b particles in the original frame S.