(30 points) Suppose that the support S of a continuous random vector (X1, X2) is given by S = {(x1, x2): 0 < x1 X1). (c) Calculate E(X1), E(X1X2), and E(X +3X1X2). (d) Describe the joint pdf, fy1,Y2 (Y1, y2), of Y and Y2. (e) Describe the pdf, fy, (y1), of Y.