Data collected at an airport suggests that an exponential distribution with mean value 2.455 hours is a good model for rainfall duration (a) What is the probability that the duration of a particular rainfall event at this location is at least 2 hours? At most 3 hours? Between 2 and 3 hours? (Round your answers to four decimal places.) at least 2 hours at most 3 hours between 2 and 3 hours (b) What is the probability that rainfall duration exceeds the mean value by more than 3 standard deviations? (Round your answer to four decimal places.) What is the probability that it is less than the mean value by more than one standard deviation?