From which country did the united states acquire most of the land in the american southwest? mexico, great britain , or france

Correct  Mexico

Context/detail:

The Mexican Cession was territory ceded (meaning given up) to the United States in 1848 after the Mexican-American War.  The territory included lands that represent the full states of California, Nevada, and Utah, as well as large portions of  Arizona and New Mexico, and about a quarter of what would become the state of Colorado.  There was also a small section of Wyoming involved.  So that represents the bulk of territory that is in Southwest of the present United States.

The US also had obtained a large portion of land from France in 1803, in what was termed "The Louisiana Purchase."  That stretch of territory was in the middle section of the present United States (not in the Southwest).  The Louisiana Purchase stretched from Louisiana northward to cover present-day states of Arkansas, Oklahoma, Missouri, Kansas, Nebraska, Iowa, and more. It did include portions of what would become Western states of New Mexico, Colorado, Wyoming and Montana.

mexico i just got it right

in february 1787, congress decided that a convention should be convened to revise the articles of confederation, the nation’s first constitution. in may, 55 delegates came to philadelphia, and the constitutional convention began. debates erupted over representation in congress, over slavery, and over the new executive branch. the debates continued through four hot and muggy months. but eventually the delegates reached compromises, and on september 17, they produced the u.s. constitution, replacing the articles with the governing document that has functioned effectively for more than 200 years.

d: their own individual powers within the new goverment