Write down the problem of cooperation for two countries, A and B, in the fight against climate change and use a payoff matrix as in the case of the prisoner's dilemma. Payoffs are Y_A(X_A, X_B) and y(X_A, X_B), where x_A and x_B can take two values: 1) if measures are taken in the country against climate change and 2) if no measures are taken. What are the conditions of the payoffs in each cell for each player so that there is a unique Nash equilibrium in which no country takes any action against climate change?