1. Workers come to a tool store room to enquire about the special tools (required by them) for a particular job. The average time between the arrivals is 60 seconds and the arrivals are assumed to be in Poisson distribution. The average service time is 40 seconds.

Determine

1. Average queue length (2marks)
2. Average length of non-empty queue (1mark)
3. Average number of workers in the system including the workers being attended (2marks)
4. Mean waiting time of an arrival (1marks)
5. Average waiting time of an arrival (workers) who waits (1marks)