How did railroads affect America's economy in the 1800's?

Railroad expansion affected the US economy by creating jobs, establishing a national market, establishing a cattle industry on the Plains, and allowing certain people to acquire great wealth through investing in the railroad.

Explanation:

every society, in order to meet the needs of it's people, has to answer three basic questions:

- what should we produce?

- how should we produce it?

- for whom should we produce it?

this questions must be answered in order to, option b, aid in production decisions.

every country can't produce everything, no matter how rich their land is. it may be a matter of technology, resources or geographical conditions. so, these three questions must be resolved in order to get the most of the production of each land.

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