Help please In what modern countries did the Aztec's civilization exists?

Here you go

Explanation:

Aztec, self name Culhua-Mexica, Nahuatl-speaking people who in the 15th and early 16th centuries ruled a large empire in what is now central and southern Mexico. The Aztecs are so called from Aztlán (“White Land”), an allusion to their origins, probably in northern Mexico.  

a. theta waves. this is because the person is in a light sleep which means the brain waves would show these kind of waves.

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