The number of phone calls arriving at a call center on a time interval of length t has the probability distribution (vt)* e-(vt) f (x) = x = 0, 1, 2, ... x! which is a Poisson distribution with...

Extracted text: The number of phone calls arriving at a call center on a time interval of length t has the probability distribution (vt)* e-(vt) f (x) = x = 0, 1, 2, ... x! which is a Poisson distribution with parameter A = vt. The average number of calls arriving at a telephone is 30 calls per hour. (a) What is the probability that none will arrive in a three minute period? (b) What is the probability that more than four will arrive in a five minute interval? (c) Consider the time interval between two phone calls. What is the distribution of this random variable?