Consider alternating-offer bargaining as discussed. Xenia and Zeno are dividing a pie of size 1. They are both exponential discounters but Xenia is more impatient than Zeno. Xenia's discount factor (delta) is 1/2 and Zeno's is 2/3. a. Suppose there are three periods and Xenia can make the first and the last offer and Zeno the second offer. In a subgame-perfect equilibrium how are they going to divide the pie