Mrs. Li is a very popular hair salon. It offers high-quality hair-styling and physical relaxation services at a reasonable price, so it always has unlimited demand. The service process includes five activities that are conducted in the sequence described below. (The time required for each activity is shown in parenthesis): Activity 1: Welcome a guest and offer homemade herb tea. (10 minutes) Activity 2: Wash and condition hair. (10 minutes) Activity 3: Neck, shoulder, and back stress release massage. (10 minutes) Activity 4: Design the hair style and do the hair. (25 minutes) Activity 5: Check out the guest. (5 minutes) Three servers (S1, S2, and S3) offer the services in a worker-paced line. The assignment of tasks to servers is the following: S1 does Activity 1. S2 does Activities 2 and Activity 3. S3 does Activities 4 and Activity 5. a) Which server is the bottleneck of the process? b) What is the utilization of server 2? c) What is the average labor utilization of the servers? Assume the process operates at its capacity. d) Assume a wage rate of $18 per hour. What are the direct labor costs for one guest? e) To increase the service rate, Mrs. Li is considering two alternatives: Alternative I: To hire a new employee to help anyone (and only one) of the servers without changing the tasks performed by each server. Alternative II: To redesign the assignment of tasks to servers. For this, Mrs. Lis is evaluating to reassign Activity 5 from S3 to S1. What would be the costs of direct labor of serving one guest under each of the two alternatives? Assume that the system operates at its capacity. Explain why?