Which of the following is true of the time measurement systems used by ancient mesoamerican and south american cultures a. the incas, aztecs, and mayans all had calendars. b. the incas and aztecs had calendars, but the mayans did not. c. the incas and mayans had calendars, but the aztecs did not. d. the incas had calendars, but the mayans and aztecs did not

A.The Incas, Aztecs, and Mayans all had calendars.

Explanation:

The ancient civilizations of Meso America developed precise written calendars and of these the Mayan calendar is the most sophisticated. It was the center of his life and his greatest cultural achievement. Throughout history, people have felt the need to have a fixed point to start their calculations of time. To this end, the initial point has usually been determined either by using a historical event (the birth of Our Lord Jesus Christ) or by a hypothetical event (the date of the creation of the world).

- three-quarters or two-thirds..

- "the constitution provides that an amendment may be proposed either by the congress with a two-thirds majority vote in both the house of representatives and the senate or by a constitutional convention called for by two-thirds of the state legislatures."

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