A warehouse has only one loading dock manned by a three person crew. Trucks arrive at the loading dock at an average rate of 4 trucks per hour and the arrivals are Poisson distributed. The loading of a truck takes 10 minutes on an average and the loading time can be assumed to be exponentially distributed about this average. The operating cost of a truck is Rs 100 per hour and the members of the loading crew are paid at a rate of Rs 25 per hour. Assuming that the addition of new crew members would reduce the loading time to 7.5 minutes, would you advise the truck owner to add another crew of three persons?