4. [6] Consider a one-consumer one-firm economy in which u(x) = (12) (x,), w = 2 and f (z) = z. (a) [2] Illustrate this economy in an Edgeworth box. (b) [2] Derive the Pareto set of this economy. (c) [2] Fix some Pareto-efficient allocations from (b) and derive a competitive equilibrium for this economy that generates these allocations