4. Suppose F(K, L) = VK l x/f Here K represents capital, which has price 1", and L represents labour, which has price w. a. Show that F has decreasing returns to scale. b. Find the marginal rate of technical substitution between capital and labour. c. Hence, or otherwise, nd the cost-minimising long-run choice of K and L to produce a given level of output, y. d. Find the minimum cost of producing the good as a function of y and 'r and w. Discuss briey how it depends on y