The midwestern united states was an important manufacturing region throughout the early 20th century. cities such as detroit, cleveland, and pittsburgh grew because of industries like auto manufacturing and steel production. which of the following statements is true?
a. access to rivers and railroads was needed to get manufactured goods to markets.
b. millions of immigrants came to the u. s. to buy the new manufactured products.
c. the cities were located far from the natural resources needed in the factories.
d. factories in the midwest closed because of