Question 3: Utility Functions and Indifference Curves. (25 pts) (a) Consider the utility function u (X1, X2). What is meant by a monotonic transformation of the utility function? (8 pts) (b) Suppose that u1 (X1, X2) = 6x1 + 9x2. Draw the indifference curves for utility levels u (x1, x2) = 10, u (x1, x2) = 20 and u(x1, X2) = 30. (6 pts) (c) Now consider u2(X1, X2) = 2x| + 3x2. Again, draw the indifference curves for utility levels u (x1, x2) = 10, u(x1, X2) = 20 and u(x1, x2) - 30. (6 pts) (d) Is wi (x1, x2) a monotonic transformation of u2 (X1, x2)? Can both describe the same preferences? Explain. (5 pts)