A cafeteria serving line has a coffee urn from which customers serve themselves. Arrivals at the urn follow a Poisson distribution at the rate of five per minute. In serving themselves, customers take about 8 seconds, exponentially distributed. a. How many customers would you expect to see on the average at the coffee urn? (Round your answer to 3 decimal places.) Average customers b. How long would you expect it to take to get a cup of coffee? (Round your answer to 3 decimal places.) Expected time minute c. What percentage of time is the urn being used? (Round your answer to 2 decimal places.) Percentage of time % d. What is the probability that three or more people are in the cafeteria? (Round your answer to 4 decimal places.) Probability e. If the cafeteria installs an automatic vendor that dispenses a cup of coffee at a constant time of 8 seconds, how does this change your answers to a and b? (Round your answers to 3 decimal places.) Average number of people reduced by customers Time reduced by minutes