A service counter employs two servers. On average a server requires 8 minutes to process a customer and service times follow an exponential distribution. Customers arrive at the counter at the rate of 12 per hour according to a Poisson distribution. The average amount of time, in minutes, spent in the system (i.e., waiting and being served) is approximately

Select one:

A.

0.237 minutes

B.

14.22 minutes

C.

33.30 minutes

D.

22.20 minutes