How could the united states be described as a ‘melting pot’ at the end of the 19th and the beginning of the 20th century?

In a modern democracy all elected officials serve for a certain number of terms then must retire a high school sophomore and a senior citizen may vote at the polls together a united states senator votes on immigration law on behalf of your mother through indirect ballot all democracies have a two chamber system of representation united states citizens live in a direct democracy