QUESTION 4 (Burning a Bridge). Army 1, of country 1, must decide whether to attack army2, of country 2, which is
occupying an island between the two countries. In the event of anattack, army 2 may Öght, or retreat over a bridge to its mainland. Each army prefers tooccupy the island than not to occupy it; a Öght is the worst outcome for both armies. Modelthis situation as an extensive form game with perfect information and show that army 2 canincrease its subgame perfect equilibrium payo§ (and reduce army 1ís payo§) by burning thebridge to its mainland (assume this act entails no cost), eliminating its option to retreat ifattacked. (In drawing the game tree, you can specify arbitrary numbers to represent di§erentoutcomes, as long as the resulting outcomes Öt the above description).