What was the last territory the United States gained as it expanded westward and was it acquired?

alaska

Explanation:

apartheid, (afrikaans: “apartness”) policy that governed relations between south africa's white minority and nonwhite majority and sanctioned racial segregation and political and economic discrimination against nonwhites. people should not get this wrong. i was just answering a question.

in the 1950s, country music came into its own before rock-n-roll took off in the 60s while jazz and classical music continued to innovate