3. Let X and Y follow a joint distribution with pdf f($:y) = 12y\") S y S 9: 51. . Find the marginal density of X , fX(a:). . Find the marginal density of Y, fy(y). Find the conditional density of X given Y = y, f(a:|Y = 3;). Find E(X|Y = y). Find E(X). Find 130/2). . Find the probability that X