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.  

the answer is b. 300t + 3/2xt

"a government in which power is divided between state and national levels". federalism is a system of government in which entities such and state and province, share power with the national government.