can i have some help please?

Customers enter the camera department of a store at the average rate of five per hour. The department is staffed by one employee, who takes an average of 4.0 minutes to serve each arrival. Assume this is a simple Poisson arrival, exponentially distributed service time situation. Use Exhibit 10.9. a-1. As a casual observer, how many people would you expect to see in the camera department (excluding the clerk)? (Round your answer to 2 decimal places.) a-2. How long would a customer expect to spend in the camera department (total time)? (Round your answer to 1 decimal place.) b. What is the utilization of the clerk? (Round your answer to 1 decimal place.) c. What is the probability that there are more than two people in the camera department (excluding the clerk)? (Round your intermediate calculations to 3 decimal places and final answer to 1 decimal place.) d. Another clerk has been hired for the camera department who also takes an average of five minutes to serve each arrival. How long would a customer expect to spend in the department now? (Round your answer to 1 decimal place.) Expected Number of Customer Waiting in Line (Lq) for Various Values of S and / exhibit 10.9