Early Americans were nomads who depended on?

From 1990 to 2008, by what percent did the world’s most developed economies cut their greenhouse gas emissions?

Which landmark supreme court case ruled that segregation by race in public education was unconstitutional? a.miranda v. arizona b.plessy v. ferguson c.brown v. board of education of topeka d.alexander v. holmes county board of education

When did martin luther king, jr. deliver his famous "i have a dream" speech? a. during the montgomery bus boycott b. during the birmingham campaign c. during his acceptance of the nobel prize d. during the march on washington