Consider a firm where the marginal product of the typical worker varies over time according to the schedule in Table 11-5 where year 0 represents the current year. In order to motivate its workers to exert their best efforts, suppose this firm plans to sequence the pay in such a way that workers receive less than their marginal product early in their career, and then more than their marginal product toward the end of their career. Why is the prohibition of mandatory retirement policies thought to decrease the likelihood firms will employ such schemes