Exercise 7.3.2 Evaluate the rst partial derivatives of the function at the given point. (a) they) = 939+er2 at (1 ,3} (f) f (1039') = $11919)\" (tr/2,1) (c) f(s,t) : s/t at (1,2) (d) POW) : 9H\"! (1,1) Exercise 7.3.3 Suppose the productivity of a country can be approximated by Y(L, K) = 1513/5 K2/5 where L is units of labour and K is units of capital. (a) Calculate YK and YL. (b) Calculate the marginal productivity of labour and the marginal productivity of capital when L = 100 and K = 55. Interpret your results.