A bus comes by every 15 minutes. The times from when a person arives at the busstop until the bus arrives follows a Uniform distribution from 0 to 15 minutes. A person arrives at the bus stop at a randomly selected time. Round to 4 decimal places where possible. a. The mean of this distribution is b. The standard deviation is c. The probability that the person will wait more than 4 minutes is d. Suppose that the person has already been waiting for 0.4 minutes. Find the probability that the person's total waiting time will be between 3.7 and 3.9 minutes e. 23% of all customers wait at least how long for the train? minutes.