8. [Change of Variables] Consider the integral y dA, where B is the region in the ry-plane which is bounded B by x + y = 2 and r + y = 3 and between y = $x and y = 2r. (a) [c] Draw the region B. (b) Consider the transformation where o = r + y and = 4. Find the inverse transformation by solving for r and y; then draw the region in the of-plane. (c) What is the jacobian of this transformation? (d) [W] Evaluate the integral