waiting line analysis

Part 1 Marcy operates a ticket booth by herself where she can serve an average of 14 customers per hour. An average of 8 customers arrive to purchase tickets each hour. The average time a customer spends waiting in line = minutes. Round to one significant digit past the decimal. What is the probability that 5 customers will arrive at Marcy's ticket booth in the next hour? Marcy's friend is going to call the ticket booth to make plans for this weekend. What is the probability that Marcy will be able to answer the phone because she is not busy helping a customer? Part 2 The average time to help a client at William's office is 4 minutes. Clients arrive at his office at a rate of 6 per hour. What is the Service Rate? Otis is heading over to William's office. What is the probability that he will find clients waiting in line (one or more in the line)? Part 3 A university instructor wants to get the average time a student spends at his office (either waiting or working with the instructor) down to 15 minutes. Students arrive at his office at a rate of 6 students per hour. The instructor can only work with one student at a time. To achieve this goal, the instructor needs to make sure the average time spent working with a student is approximately minutes