Suppose customers arrive at a service station with two servers according to a PP(). An arriving customer is routed to server 1 or server 2 with equal probability. What are the mean and variance of the time between two consecutive arrivals to the first server? Next suppose we route the arriving customers to the two servers alternately. Now what are the mean and variance of the time between two consecutive arrivals to the first server? Is the arrival process of the customers to server 1 a Poisson process?