By 1850, in the largest northern cities such as New York and Boston,

immigrants made up a large part of the population.

Explanation:

That region is closed to a Ellis Island, where the new York harbor built the station that is used to inspect the immigrants that coming into United States.

Most of these immigrants left their poor country after hearing the abundance amount of job opportunities that exist in United States due to the industrial revolution. As a result, Immigrants made up largest part of the population. By 1850, around 60% of the people who lived in these northern cities were immigrants.

answer; use multiple stimuli;