Reaper and steel plow were the machines invented by Cyrus McCormick and John Deere that made large-scale agriculture possible, especially on Midwestern prairies.
B) Reaper and steel plow
<u>Explanation:</u>
In the 1800's people used to do all the chores with their hands hence, it made farming a tough job and a lot of time consuming activity. During the industrial revolution, Cyrus McCormick invented a mechanical reaper, which would help reap big farms in very less time.
The steel plow played a very important role in the industrial revolution as the wooden plow used to be weak but John Deere's invented steel plow was strong and broke soil easily.
Men unfortunately or fortunately tend to be more aggressive and a higher percentage lean toward war, even though they end up in the dangerous fray.
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