How and why did patterns of migration affect society between 1750 and 1900?

because america, people were like hell yeah brother lets go to america and be free unlike most country's

Explanation:

Migration patterns were now more directed to places with available labor and prosperity, due to imperialism and industrialization changing where people could make a good living. People sought a place that they could have a good place to make money and live, and so people looked towards cities that had industries that needed labor. Many of those people might have come from far away or they might just have been in the country trying to farm.

Explanation:

nothing certain is known about what happened, but it seems that the country declined gradually, perhaps due to bad government, or, more likely, due to a series of bad harvests, which resulted in widespread and recurrent famine.

a.

congress passed laws allowing for free passage between states.