A small grocery market has one checkout counter. The counter clerk takes an average of 3 minutes to serve a customer. Customers arrive at the counter at the rate of 15 per hour. The manager of the store receives feedback from customers that the wait time is long and the store needs another checkout counter. The manager plans to open another checkout counter and divide the arriving customers equally between the two checkout counters. Before implementing his decision, he wants to evaluate the cost-benefit analysis. The manager estimates that opening another checkout counter would costs him R70,000 per annum. The manager also estimates that reduction in waiting time by a minute earns a revenue of R10,000 annually. Recommend whether or not the manager should open the second counter.