RentAPhone is a new service company that provides European mobile phones to American visitors to Europe. The company currently has 60 phones available at Charles de Gaulle Airport in Paris. There are, on average, 26 customers per day requesting a phone. These requests arrive uniformly throughout the 24 hours the store is open. (Note:This means customers arrive at a faster rate than 1 customer per hour.) The corresponding coefficient of variation is 1.

Customers keep their phones on average 48 hours. The standard deviation of this time is 60 hours.

Given that RentAPhone currently does not have a competitor in France providing equally good service, customers are willing to wait for the telephones. Yet, during the waiting period, customers are provided a free calling card. Based on prior experience, RentAPhone found that the company incurred a cost of $1.80 per hour per waiting customer, independent of day or night.

(b) How long does a customer, on average, have to wait for the phone? (Round your answer to two decimal places.)