Let x(t) be a Poisson process with rate and fix instants t1 = 0 ms, t2 = 3 ms, t3 = 4 ms, t4 = 5 ms
a) Find the probability that exactly 2 arrivals lie in the interval (t2, t4), given that there are none in the interval (t1, t3).
b) Let be two unordered arrivals in the interval (t3, t4), find the mean and variance of their difference