Simulation Systems Modeling (Software used: Rockwall ARENA) concepts

1. A laundromat has 15 washing machines, 5 dryers, a bill changer and a soap vending machine. There is no attendant

a. Give system components,

b. Give system parameters(some in description, some not),

c. Relationships,

d. variable

2. A production process has two machines in series. After a job has been processed on the second machine, the operator examines the finished part and determines if it is good or defective; defective parts are reprocessed through both machines; the probability of a defective part is 0.1. Parts arrive every 5 to 7 (uniform distribution) minutes; each machine has normally distributed processing times with a mean of 5 minutes and a standard deviation of 1 minute.

a. Give the ARENA model

b. what can be said about the theoretical utilization of the servers

please help its concepts based and drawing Thanks!