16. Consider an infinitely repeated game where, in each round, two firms compete a la Bertrand in a market with inverse aggregate demand function p(g) = 300 2g. The firms have identical marginal costs, 20. What is the minimum discount factor (if any) such that they can sustain the monopoly price by the \"perfect Tit-for-Tat\" strategy, defined as follows: e Choose the monopoly price in the first period Choose the collusive price if either (a) both players played the monopoly price in the previous round; or (b) both players played price equal to marginal cost in the previous round e Choose price equal to marginal cost otherwise ) 1/3 ) 1/2 c) 2/3 i3 ) None of the above options