In the 21st century, U. S. efforts to limit the development of nuclear weapons have focused on which two countries? India and Pakistan
Iraq and Afghanistan
Iran and North Korea
Israel and Saudi Arabia

Iran and North Korea

Explanation:

modern movements fear the nuclear weapons of North Korea and Iran.

while it was true that the cotton gin reduced the labor of removing seeds, it did not reduce the need for slaves to grow and pick the cotton.

explanation:

before eli whitney's invention of the cotton gin, picking and cleaning cotton was a slow, labor-intensive job. workers, usually slaves, had to pick the seeds from the cotton fibers by hand. this invention made it possible to grow large amounts of cotton on big farms and make money.