Montesquieu presented an idea for how to organize representative government that is known as

The idea is known as the Republican form. The idea is that people democratically elect those who would represent them in a government, and those people would be held accountable for what they've done if they do something opposite to the will of the people. It's the only way that a democracy can work properly because others would be impossible with that many people.

Ais your correct answer

From mexican american war , us gained new mexico.