The Louisiana Purchase and the belief in Manifest Destiny affected the United States in the 1800's by -

As a result of the deal, the U.S. gained control of the powerful Mississippi River, doubled the size of the country and affirmed the idea for many that America's "Manifest Destiny"

Explanation:

answer; ///i do believe that the correct answer is (d); ///athens had a small population;

the government paid religious orders to provide basic education to native american children on reservations. in the late 19th and early 20th centuries, the bureau of indian affairs (bia) founded additional boarding schools based on the assimilation model of the off-reservation carlisle indian industrial school.