The RTC company has technicians that go to the company production sites to fix the their advanced robot assembly systems when they breakdown. During the last 12 months, 35 robot assembly systems needed repair. Each day a robot assembly system is not working (therefore waiting to be fixed) costs the company $800 (the waiting cost rate). The average time to repair is 1 month. Each technician earns an annual salary/benefits of $89K. Assume 20 working days in a month and 12 months/ year. They currently have 4 technicians and are considering hiring one more. Answer the following questions. Complete all calculations with at least 2 decimal points.

What is the arrival rate per month? . What are the WCe when there are 4 technicians? What are the RCe when there are 4 technicians? What are the TCe if an additional tech is added? How many technicians should RTC have to minimize total costs?