c) Suppose instead that the treaty is expected to be in force indefinitely into the future and that India and Pakistan receive the payoffs described each year the treaty is in force. The two countries know that if either country defects on the agreement the other country will punish the cheater by defecting in return. Assume that both countries' discount rates are 0.9. How many periods would India have to punish Pakistan in order to make compliance worth more to Pakistan than cheating? (Show your work)