The calendars produced by both Mayan and ancient Mesopotamian civilization were

They both created accurate calendar.

Explanation:

Cuneiform is one of the earliest writing system developed in Mesopotamia. The Maya calendar based on the Sun, the Pleiades star groups, the Moon, and other planets. The Mayan and ancient Mesopotamian civilizations both had calendars.

the constitution gives congress the power to regulate commerce "among" the several states.