Answer:
The existence of isotopes contradicts part of Dalton's original atomic theory because he said all atoms of a given element are identical have the same mass size and chemical properties.
Explanation:
In the late 1800s, people in many parts of the world decided to leave their homes and immigrate to the United States. Fleeing crop failure, land and job shortages, rising taxes, and famine, many came to the United States because it was perceived as the land of economic opportunity.
1)estas
2)esta
3)estan
4)estare
5)estamos
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