Recall Exercise S7 from Chapter 4, about an old lady looking for help crossing the street and two players simultaneously deciding whether to offer help. If you did that exercise, you also found all of...

Recall Exercise S7 from Chapter 4, about an old lady looking for help crossing the street and two players simultaneously deciding whether to offer help. If you did that exercise, you also found all of the pure-strategy Nash equilibria of the game. Now find the mixed-strategy equilibrium of the game.