Sample response: The general lesson from the reading is that inventing a useful product takes time and perseverance. You have to experiment, fail, and retry your ideas until you succeed.
I think the first quote best develops the central idea that African Americans have been intentionally block from voting in election.
"Every device of which human ingenuity is capable, has been used to deny this right."
Meaning that every device humans have have been used to deny the right to vote in elections.