Consider the following utility functions: 'Cobb-Douglas' utility function: u(cl, (:2) : (ga la C2 'lsoelastic' utility function: u(cl, (:2) : ln(c1) + 1 o: Where a is an exogenous parameter that determines the curvature of the utility function with respect to each argument. Assume that consumption must be positive.1 (a) Compute the rst and second-order partial derivatives with respect to each argument of the above utility functions. (b) For the CobbDouglas utility function, show that marginal utility is positive and diminishing with respect to each argument if 0 1. (c) For the Isoelastic utility function, show that marginal utility is positive and dimin- ishing with respect to each argument if 0: > 0, but not if 0 > 0