Which circumstance was most directly responsible for the rapid growth of the railroad industry? inventors developed air brakes and more efficient train-car connectors builders agreed on a universal width for train tracks railroad owners sold stock to investors to finance the construction of railroads pullman began manufacturing cars for overnight travel

Option C- Railroad owners sold stock to investors to finance the construction of railroads

This was the most important reason that was directly responsible for the rapid growth of the railroad industry  because constructing railways was a very expensive capital investment business. Hence railroad owners sold stock to investors to finance the construction of railroads.

        i'm fairly sure that the correct answers are 2 and 3.

        i used both my knowledge of world history and the process of elimination to obtain these answers. option 1 cannot be a possible selection because the mandate of heaven belongs to ancient chinese philosophical belief. option 4 sounds like it would benefit the region than detriment it. however, both 2 and 3 explain a potential reason for what could have contributed to the fall of the roman empire.

      hope this ! if i were you, i'd get a second opinion, because i haven't taken this course for a year. best of luck!

***websites that me understand the curriculum better last year are and ***

hacida

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