How did congress try to change the buying and selling of slaves? a. by forbidding the sale of slaves in the united states b. by passing a law assisting slaves in gaining their freedom in the north c. by forbidding the sale of slaves to foreign places d. by heavily taxing the importation of slaves into the united states (a and d are wrong but i’m not sure what the answer is )

The correct answer is option b. "by passing a law assisting slaves in gaining their freedom in the north". The Congress was trying to regulate the buying and selling of slaves, when the Missouri Compromise was stated in 1820. This bill prohibited slavery north of the southern boundary of Missouri, which assisted slaves to pursue their fight for freedom.

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.