2. [10 pts.] Suppose the arrival of telephone calls at a switch can be modeled with a Poisson PMF. That is, if X is the number of calls that arrives in t minutes, then for k- 0,1,...: k! where is the average arrival rate in calls/minute. Suppose that the average rate of calls is = 10 per minute. a. What is the probability that fewer than three calls will be received in the first 6 seconds? b. What is the probability that fewer than three calls will be received in the first 6 minutes