Answer :
The correct answer is option 4, Stepheson designed a standard-size railroad track.
- George Stephenson established a standard railroad gauge of 4 feet 8 12 inches, which is now used by the majority of the world's railroads.
- It brought products from eastern industry to the growing population east of the Mississippi, just as it opened up markets from the west coast and Asia to the east.
- As industry mined the vast resources of the middle and western continents for use in production, the railroad ensured a production boom.
- Railways eventually reduced the cost of transporting many different types of goods over long distances. These transportation advancements aided settlement in North America's western regions. They were also critical to the country's industrialization. The increase in productivity that resulted was astounding.
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