The United States bought Alaska in 1867 to

keep Russia from expanding toward the US mainland.
stop other countries from taking over the territory.
control the territory’s abundance of resources.
open a critical trade route with the Far East.

Hello again the correct answer to this A. keep Russia from expanding toward the US mainland.

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d. the great plains       hop3 this yo

the treaty of brest-litovsk was a peace treaty signed on 3 march 1918 between the new bolshevik government of russia and the central powers (german empire, austria-hungary, bulgaria, and the ottoman empire), that ended russia's participation in world war i.