ABCD currently has one outside drive-up teller. It takes the teller an average of four minutes (exponentially distributed) to serve a bank customer. Customers arrive at the drive-up window at the rate of 12 per hour (poisson distributed). The bank operations officer is currently analyzing the possibility of adding a second drive-up window at an annual cost of $20,000. It is assumed that arriving cars would be equally divided between both windows. The operations officer estimates that each minutes reduction in customer waiting time would increase the banks revenue by $2,000 annually.

1. Is it cost effective to install a second drive-up window? (Show calculations to support your answer.)
2. What other factors should be considered in the decision besides cost?