Railroad tycoons were the early industrial pioneers amassing or overseeing construction of many large railroads through the early 20th century. The names of the leaders are, James Hill, Jay and George Gould, Cornelius Vanderbilt, Edward Harriman, and Collis P. Cornelius Vanderbilt was a famous industrialist who worked in railroads and shipping.
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The answer is A. movement of energy through space or a medium
