45. Carloads of customers arrive at a single-server station in accordance with a Poisson process with rate 4 per hour. The service times are exponentially distributed with rate 20 per hour. If each carload contains eitherI mage, or 3 customers with respective probabilitiesI mage, andI mage, compute the average customer delay in queue.

46. In the two-class priority queueing model of Section 8.6.2, what is

? Show that is less than it would be under FIFO ifI mage and greater than under FIFO ifI mage.