consider a service center consisting of two servers, each working at an exponential rate of two customers served per hour. assume customers arrive to service center according to a possion rate of three per hour, and the service center can hold at most four customers(including the customers being served)a)what fraction of potential customers enter the system?b)what would be the answer to part(a) if there were only a single server that can serve customers twice as fast (i.e, with service rate four customers per hour)?c)now suppose that the service center consists of two separate lines, one for each server. each line can hold at most customers, including the custommer being served. for simplicity, suppose that an arriving customer chooses a line uniformly at random. if the line they chose is full, the customer leaves.for this system, calculatethe fraction of potential customers that enter the system.