calls to a fire station arrive according to a Poisson process with rate 0.5 per hour, and the time required to respond to a call, return to the station, and get ready to respond to the next call is uniformly distributed between 1/2 and 1 h. If a new call comes before the Dryden fire department is ready to respond, the Ithaca fire department is asked to respond. What fraction of calls must be handled by the Ithaca fire department