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Use the following for questions 36-40 Melanie owns a popular donut shop that is open from Sam to noon, 7 days a week. She has one cashier who focuses on assisting customers purchasing donuts. Her cashier is paid $15/hour. Melanie has determined her shop meets the conditions for M/M/1 analysis. Assisting a customer takes 5 minutes on average. Customers arrive on the average of 8 per hour. 36. What is a customer's average waiting time before placing their order? A. 10 minutes B. 12 minutes C. 5 minutes D. 30 minutes 37. When a customer enters the line, what is the probability that there is at least one person already in line in front of them? A. 80% B. 67% C. 35% D. 20% 38. What is average number of customers in the queue? A. 1.33 B. 2 C. 0.25 D. 0.17 39. What is the average number of customers in the store? A. 1.33 B. 2.0 C. 0.25 D. 0.17 40. Melanie decides that it's in her best interest to open up a second cashier who will be paid at the same rate and expected to service customers at the same rate. Customers will stand in one line and go to the next available cashier as they become open. Customers' waiting cost in line remains at $75/hr. What is the average number of customers in the store with a second cashier? A. 1.33 B. 2.0 C. 0.08 D. 0.75