What factor contributed to chicago's rise as a steel making and manufacturing center in the late 1800's? a. railroads were built b. the population increased c. corporate farms delined d. mixed-crop farms increased

The railroads :) 

Especially in 1848, when workers began to build the Galena & Chicago Union Railroad. 

Here's some info. http://encyclopedia.chicagohistory.org/pages/653.html
Hope this helps

France played a key role in the american revolutionary war (american war of independence; 1775–1783). motivated by the ideals of the new nation which were inspired by the french enlightenment, as well as its long-term rivalry with britain and so as to avenge their territorial losses during the french and indian war, france secretly began sending supplies to the americans in 1775.