A. Rookie, an assistant professor of human relations at the Jackson School of Public Affairs, wants to teach his class the value of cooperation. He divides the class into three teams. Each team must select a color, either red or green. If all three teams select green, Rookie will pay each team a dollar. If two teams select green, these two teams will pay the other team a dollar each. If one team selects green, it must pay $2 to each of the other teams. If all three teams select red, each team pays Rookie a dollar. After 10 rounds of the game, Rookie discovers himself $24 richer. What has happened?