An observer in a coasting spacecraft moves toward a mirror at speed v relative to the reference

Question:

An observer in a coasting spacecraft moves toward a mirror at speed v relative to the reference frame labeled by S in Figure P39.70. The mirror is stationary with respect to S. A light pulse emitted by the spacecraft travels toward the mirror and is reflected back to the craft. The front of the craft is a distance d from the mirror (as measured by observers in S) at the moment the light pulse leaves the craft. What is the total travel time of the pulse as measured by observers in?
(a) The S frame and
(b) The front of the spacecraft?

An observer in a coasting spacecraft