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a) Consider the Ramsey-Cass-Koopmans model where k at time 0 (which-as always-the model takes as given) is at the golden-rule level: k(0) = kGR. Sketch the paths of c and k. 95 (b) Consider the same initial situation as in part (a), but in the version of the model that includes government purchases. Assume that G is constant and equal G. Crucially, G is strictly less than f(kGR) (n + g)kGR and strictly greater than f(k) (n + g)k (where k is the level of k on the balanced growth path the economy would have if G were constant and equal to 0). Sketch the paths of c and k. (Hint: This question is hard but can be answered by thinking things through slowly and carefully.)