Mr K's Is a Very Popular Hair Salon

Mr. K's 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.
-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.