Cars coming along Magnolia Street come to fork in the road and have to select either Willow Street or Main Street to continue. Suppose that the number of cars which arrive at the fork in unit time has Poisson distribution with parameter ? = 4. A car arriving at the fork chooses Main Street with probability 3/4 and Willow Street with probability 1/4. Let X be the random variable which counts the number of cars that, in a given unit of time, pass by Joe's Barber Shop on Main Street. Compute the distribution of X?