Between 1820 and 1850, which factors affected European immigration to America?
1.New laws restricted the arrival of immigrants from Russia.
2.New laws restricted the arrival of immigrants from Italy.
3.It became easier and cheaper to immigrate to the United States.
4.It became less expensive for all immigrants to buy property in the US.

3. It became easier and cheaper to immigrate to the United States.

Explanation:

This is a period when many Europeans immigrated on East Coast. People came from different parts of Europe, but mostly Ireland. The main reason was the great famine that struck that country. In comparison to previous period it was much cheaper to immigrate to States, which was regarded as land of opportunities.

dirty, contaminated water

contaminated food,

chlostrophobic living spaces,

mice infestation,

etc,