PLEASE Answer A-2, and D with clear work and clear answers

Customers enter the camera department of a store at the average rate of nine 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.) Answer is complete and correct. Number of people 1.50 a-2. How long would a customer expect to spend in the camera department (total time)? (Round your answer to 2 decimal places.) X Answer is not complete. Average total time minutes b. What is the utilization of the clerk? (Round your answer to 1 decimal place.) Answer is complete and correct. Utilization 60.0 % 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.) Answer is complete and correct. Probability 21.6 % d. Another clerk has been hired for the camera department who also takes an average of 4 minutes to serve each arrival. How long would a customer expect to spend in the department now? (Round your answer to 1 decimal place. Use the closest value of Nu in Exhibit 10.9 when determining Lq (i.e., do not interpolate).) Answer is not complete. Average total time minutes