Assume T is the time between phone calls at computer tech help center. They average 3.7 phone calls per minute. (You don't know the exact distributions, so employ the one(s) that are most appropriate to answer the following questions.)
a. if a phone call just occurred, determine the probability that there won't be another phone call for at least the next 30 seconds?
b. Determine the probability that there will be at least 2 phone calls in the next minute?