An observer S who lives on the x-axis sees a flash of red light at x = 1210 m, then after
4.96 μs, a flash of blue at x = 480 m. Use subscripts R and B to label the coordinates of
(a) What is the velocity relative to S of an observer S’ who records the events as
occurring at the same place?
(b) What is the measured time interval between these flashes in S’. Use the invariant