Use game theory to model everyday interactions. Suppose you and a partner play the following game. You both are situated with your backs to each other, 20 feet apart. You have a basketball and a softball in front of you. Your partner has a softball glove in front of them. Without knowing what your co-player has selected, you both will simultaneously turn around prepared to play catch with whichever equipment you have each chosen. How many Nash equilibria are in this game? Remember, an outcome is a Nash equilibrium if nobody has a profitable unilateral deviation; if no one has reason to be the only one to change what they're doing.