The cities of new york, baltimore and philadelphia began to become wealthy in the late 1600s because of what economic activity

This question is incomplete, here´s the complete question.  

The cities of New York, Baltimore, and Philadelphia began to become wealthy in the late-1600s because of what economic activity?

A) trading

B) slavery

C) rice farming

D) tobacco farming

A) trading

Explanation:

British Mercantilism was a key element for the colonial cities in the United States to prosper. The biggest cities took an especific economic role in the trade with Europe. While New York most important trade were flours and furs, Philadelphia traded on meat, wheat, and lumber,  and Baltimore eventually prospered by developing the flour-exporting trade.

answer: b.

explanation:

first industrial revolution - the first wave of the industrial revolution lasted from the late 1700s to the mid-1800s. it industrialized the manufacture of textiles and began the move of production from homes to factories. steam power and the cotton gin played an important role in this period.