Which research model refers to the study of an individual, group, or community over a predetermined period? a. cross-sectional model b. sectional model c. cross-sequential model d. longitudinal model

Arecession is the total value of all goods produced in a country in a given year total value of all goods and services produced in a country in a given year total amount of money earned in a nation over a specific period of time none of the answers are correct.