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How did rhe transcontinental railroad effected westward migration

What was one cause of the decembrist revolt? a. the desire for a constitutional monarchy b. the need for workers’ reforms c. the creation of a new railway line d. the outcome of the crimean war

What did the marshall plan do ? apex a.send aid to countries in europe b.sent atomic weapons to asia c.sent more ships to the pacific d.sent aid to the soviet union answer ; is a