What conditions prevented cortes from defeating aztecs in 1519, but enabled him to prevail in 1521

In at least two paragraphs, discuss the differences between the principles of republicanism and democracy. explain whether you think the united states is more of a republic or a democracy. refer to at least one example from the constitution.

Nationalism led to major conflicts following world war i, especially when:

The information box says that the han added 4,000 miles of wall.refer to the mileage scale.how can this be true?