these answers are wrong, please come up with the right answers

Customers arrive at Rich Dunn's Styling Shop at a rate of 2 per hour, distributed in a Poisson fashion. Service times follow a negative exponential distribution, and Rich can perform an average of 8 haircuts per hour. a) The average number of customers waiting for haircuts = customers (round your response to two decimal places). b) The average number of customers in the shop = customers (round your response to two decimal places). c) The average time a customer waits until it is his or her turn = minutes (round your response to two decimal places). d) The average time a customer spends in the shop = minutes (round your response to two decimal places). e) The percentage of time that Rich is busy = percent (round your response to the nearest whole number)