Final answer:
The railroad companies received money, tax dollars, and land in exchange for constructing the railroad.
Step-by-step explanation:
In exchange for constructing the railroad, the railroad companies received money, tax dollars, and land. The government provided financial assistance in the form of loans, grants, and subsidies to the railroad companies to support their construction projects. The companies also acquired large parcels of land alongside the railroad tracks, which they could sell or develop for profit.
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