Respuesta :

Alaska: On March 30,1867 the United States reached an agreement to purchase Alaska from Russia for a price of $7.2 million. the treaty with Russia was negotiated and signed by secretary of state William Seward and Russian minister to the United States Edouard de Stoeckl.

Hawaii: in 1898 the Spanish-American war broke out, and the strategic use of the naval base at pearl harbor during the war convinced Congress to approve formal annexation. two years later, Hawaii was organized into a formal U.S. territory and in 1959 entered the United States as the 50th state