How did the aztecs use alliances to build their empire?

Explanation is in the file

tinyurl.com/wpazsebu

This article I read stated that ¨The Aztecs built alliances, or partnerships, to build their empire. The Aztecs made the people they conquered pay tribute, or give them cotton, gold, or food. The Aztecs controlled a huge trade network. Markets drew buyers and sellers from all over the Aztec Empire.¨

answer; researchers typically cannot control people's sexual behaviors as would be necessary in an experiment;

answer; i believe its jutland peninsula and scandinavian peninsula;