21.)Steam power, the growth of railroads, free enterprise, and mass production lead to a decrease in

A. the costs of goods.

B. the number of farms.

C. leisure time.

D. the wages of workers.

Which answer best describes the u.s. national road? it ran from atlanta to baltimore and followed the railroad. it ran from new york to chicago and was made from wooden planks. it ran from massachusetts to ohio and ran parallel to the canal system. it ran from maryland to illinois and was made using macadam construction.