|Question||Characterize each of the following as a positive sum game, a zero-sum game, or a negative-sum game.
a. You play a card game in your dorm room with three other students. Each player brings $5 to the game to bet on the outcome, winner take all.
b. Two nations exchange goods in a mutually beneficial transaction.
c. A thousand people buy $1 lottery tickets with a single payoff of $800.