Suppose we have a discrete random variable X with the following probability mass function X 0 1 2 3 4 5 6 f(x) 1/64 /64 15 /64 20 15 /64 6 /64 1. (a) Using the plot (x, y) function, graph this discrete distribution. (b) What is its expected value? 2. Compute the variance. For finding sums, you can use the sum(x) function