Two ballpoint pens are selected at random from a box that contains 3 blue pens, 2 red pens, and 3 green pens. If X is the number of blue pens selected and Y is the number of red pens selected have the joint probability mass function p(x, y) as shown below. Then, verify that the column and row totals are the marginal distributions of X and Y, respectively. the column and row totals given below are the marginal distributions of X and Y, respectively.