**Q 1**. Customer arrive at a ticket counter at a rate of 50 per hr and tickets are issued

in the order of their arrival. The average time taken for issuing a ticket is 1 min.

Assuming that customer arrivals from a Poisson process and service times and

exponentially distributed, the average waiting time is queue in min is

**(A)** 3

** (B) **4

**(C) **5

**(D) **6

**Answer: (C )**

**Explanation:**