Flow of trafic at a certain trafic corner is modeled as a sequence of bernoulli trials by assuming that the probability of a car passing during any given second is a constant p. assume that the bernoulli trials at each second is independent of any other trials. suppose a pedestrian can cross the street only if no car is to pass during next 3 seconds. let x a random variable denoting the waiting time of the pedestrian at that corner (a) find p(x 1). (b) find p(x = 4).