Which of the following statements about the ultimatum game is correct? The Nash equilibrium is for the proposer to offer $5 and the responder to accept. O The Nash equilibrium is for the proposer to offer $0 and the responder to accept. O In real world experiments, offers of about $2 are the most common. O Reciprocity, which underlies the ultimatum game, helps to explain why employers often provide benefits to their workers beyond the minimum required