One way to set up the system of synchronized clocks in a frame S, as described at the beginning of Section 15.4, would be for the chief observer to summon all her helpers to the origin 0 and synchronize their clocks there, and then have them travel to their assigned positions very slowly. Prove this claim as follows: Suppose a certain observer is assigned to a position P at a distance d from the origin. If he travels at constant speed V, when he reaches P how much will his clock differ from the chief's clock at 0? Show that this difference approaches 0 as V→ 0.