I am working on this problem and I believe I got questions 1-3 right but I am stuck on how to solve for 4-5. Can you provide guidance?

The hematology lab manager has been receiving complaints that the turnaround time for blood tests is too long. Data from the past month shows that the arrival rate of blood sample to one technician in the lab is 5/hour and the service rate is 6/hour. Use queueing theory and assume that both rates are exponentially distributed and that the lab is at steady state to answer the following questions:

1.What is the capacity utilization of the lab?

5/6=.8333 or 83%

2.Average number of blood samples in the lab? 5/6-5 = 5/1 = 5

3.Average time that a sample waits in the queue? 5/6(6-5) = 5/6*1 = 5/6 = 83.33/hr

4.Average number of blood samples waiting for testing?

5.Average time that a blood sample spends in the lab?