Question 4 [16 points] Consider an economy with n = 3 goods. The utility function of the representative consumer of the economy is 6/8 - 1/8 U(X1, X2, X3) = X1 X2 X3 where x, is the amount of good i (assume x1, x2, x3 are all positive). (a) [4 points] Making a suitable monotonic transformation, show that the preference of the consumer can be presented by a utility function #(x1, x2, x3) that is separable in x1, X2, X3