Used today by much of the world, the Gregorian calendar is based on A. the ancient Hebrew calendar.
B. the Islamic calendar.
C. the cycles of the moon.
D. the movement of Earth around the sun.

Acountry’s gdp is the total dollar value of all final goods and services produced within a country’s borders in a given year. it also determines how countries are classified. which of the following is not a classification based on gdp? a. developed b. developing c. least-developed d. potentially developing