Suppose that c=0, the discount factor is ρ (rho), and demand is constant elasticity, y = p^-η. (a) Write the equilibrium conditions for the competitive firm and the monopoly in this case. (b) For the monopoly equilibrium condition to be sensible, what restriction must be imposed on η? Provide the economic explanation for this restirction. (c) Compare the level of period-0 sales under competition and monopoly.