Answer:
The railroad increased commerce by making shipping easier and cheaper.
Explanation:
The first transcontinental railroad in the United States is the name of a railroad line through the United States that united the city of Omaha (Nebraska) with Sacramento in the 1860s, thus uniting the Eastern rail network of the United States. with California, on the Pacific coast. It ended with the famous Golden Spike ceremony held on May 10, 1869 in Promontory, Utah, creating a nationwide mechanized transportation network that revolutionized the population and economy of the American West.
Authorized by the Pacific Railroad Act of 1862 and strongly supported by the federal government, it was the culmination of a decades-long movement to build this line and was one of the greatest achievements of the presidency of Abraham Lincoln, completed four years after his death. The construction of the railroad required enormous feats of engineering and work to cross plains and high mountains by the railway companies Union Pacific and Central Pacific, the two companies that built the line to the west and to the east respectively.
This railroad was considered the greatest American technological feat of the 19th century. It served as a vital link for industry, commerce and travel, uniting the East and West halves of the late nineteenth century of the United States. The transcontinental railroad ended quickly with the romantic lines of diligence, much slower and riskier, that had preceded it. The subsequent advance of the so-called "manifest destiny" and the proliferation of the "iron horse" through the lands of the indigenous natives greatly accelerated the fall of the great Indian culture of the great plains.