4.8.3) Calls to a telephone system follow a Poisson distribution with a mean of 3 calls per minute.

a) What is the name applied to the distribution and parameter values of the time until the 8^th call?

b) What is the mean time until the 8^th call?

c) What is the mean time between the 3^rd and 4^th calls?

d) What is the probability that exactly two calls occur within one minute?

e) If 5 separate one-minute intervals are chosen, what is the probability that all intervals conatin more than three calls?