List two factors that the us shift to an industrial economy during the gilded age

Two of the major factors were the railroads and the invention of the assembly line. With the finishing of the transcontinental railroad some 30 years earlier, the US had a nation that was linked coast-to-coast and was able to transport goods in a fraction of the time it previously could. With the invention and perfection of assembly line processes, those goods could now be produced in a fraction of the time, as well.

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