They made Channels underground a lined with clay to prevent sepage in the surrounding soil. They were a big contribution and we still do something inspired by that today.
"They promised bills and laws in favor of immigrants in exchange for votes" is the one way among the following choices given in the question that political machines, such as Tammany Hall, work with and for immigrants.
1.warts and all
I'm still trying to figure out number two
The main way in which the passage of the Voting Rights Act of 1965 affected voter registration rates in the United States in the decades that followed was that "<span>C. African American voter registration rates became lower than white registration rates," although they did increase from the previous level. </span>
The free blacks were persuading slaves to rebel.
