Answer:
The main reason for the growth of cities and suburbs in late 1800s and early 1900s was transportation innovations such as trolleys,streetcars and elevated roads.
Explanation:Mass transit system evolved.This helped large number of people to commute to work from distant places.Earlier transportation was not developed so it was hard for people residing in villages to commute to cities in search of their work .They had to work in villages in to earn a livelihood.Economic condition of farmers was poor .But transportation system was not developed enough to enable villagers to move to cities but with good and easy transportation they move to cities and settled their.This led to the growth of cities.
Industries began to grow rapidly in cities.Wealthier families move outside the cities and created the suburbs.Industrialization created many jobs and urged many more people to move to cities.New large cities such as Denver ,Chicago,Cleveland developed inland along new transportation routes.
Abolitionists employed each of these techniques. The underground railroad was a system used to help slaves escape. Religion played a critical role in helping people realize the immorality of slavery and armed force was used in certain cases (occasionally resulting in even greater problems or backlash from slave owners).
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