You are the manager of a local bank where three tellers provide services to customers. On average, each teller takes four minutes to serve a customer. Customers arrive, on average, at a rate of 40 per hour. Having recently received complaints from some customers that they waited a long time before being served, your boss asks you to evaluate the service system. Specifically, you must provide answers to the following questions: The average utilization of the three-teller service system is rho = (Enter your response rounded to four decimal places.)