Please show formula

A small coffee shop has a single barista. Because the shop is small, there are no tables or chairs. Consequently, customers wait in a single line to order and receive their coffee and leave the shop as soon as their order is received. Customers arrive at the shop at the rate of 10 per hour. It is estimated that the barista needs, on average, 150 seconds (exponentially distributed) to serve each customer. a. The average server utilization is (Enter your response rounded to two decimal places.) b. The average line length in the coffee shop is c. The average time spent in line is minute(s). (Enter your response rounded to one decimal place.) customer(s). (Enter your response rounded to two decimal places.) (Enter your response rounded to one decimal place.) e. The average time spent by customers in the coffee shop (includes waiting time and service time) is minute(s). (Enter your response rounded to one decimal place.) d. The average number of customers in the coffee shop is