What does Marginal Benefit mean

Persons who have not yet attained the legal age of consent under the applicable laws in the jurisdiction in which the research was approved.persons who are under 18 years of age.persons who have not yet attained the legal age of consent under the applicable laws in the jurisdiction in which the research will be conducted.persons who are under 21 years of age.

Mankiw attributes – chapter 1 and his 10 principles – differences in living standards within a countryover time and across countries at a moment in time to: a. the presence or absence of inflation and unemployment.b. the allocation of resources between private markets and the public sector.c. those that have dealt successfully with the efficiency v. equality tradeoff and those that haven’t.d. differences in productivity.e. ones that think at the margin and respond to incentives and those that don’t.

What is the purpose of figurative language? what jobs does it do?