Question 4 [16 points] Consider an economy with n = 3 goods. The utility function of the representative consumer of the economy is U(x1, x2, x3) = x1113 x26/8 x31/8 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 u(xi, x2, x3) that is separable in x1, x2, x3. For the rest of the question, work with the function u('x1, x2, x3) obtained in (a). The economy has L units of labour that the representative consumer supplies. There are three sectors 1, 2, 3 in the economy, with sector 1' producing good 1'. Each sector has a competitive fringe of rms. Initially rms in all sectors use the existing technology (traditional mode) in which 1 unit of labour can produce 1 unit of good and the wage is 1. There is a new technology (modern mode) in which 1 unit of labour can produce t > 1 units of the good. The modern mode pays higher wage l + v. It is known that L = 400, t = 4 and 1 + v = 2 (so that v = 1). (b) [12 points] Suppose sectors 2,3 are non-industrialized (that is, all rms in sectors 2,3 use traditional mode) and sector 1 is industrialized (that is, all rms in sector 1 use modern mode). Showing all steps of your work, determine (i) the income of economy and (ii) the demand for each of the goods 1, 2, 3