Answer:
Option: B) Cotton gin
D) Threshing machine
Explanation:
By the invention of the cotton gin by Eli Whitney, bought a change in America in cotton production. It gave rise to the Southern cotton plantation. The purpose of this machine was to remove the seeds from the cotton fiber.
The threshing machine, invented by Andrew Meikle, a Scottish mechanical engineer, in 1786 in America. The purpose of this machine is to remove the husk from the grains of wheat. Before the coming of this machine, the husk was removed by hand, which took time and energy.
