Why did southern plantation owners need slaves for labor

mainly cotton

Explanation:

cotton had many thorns, so no one wanted to do the work. when slaves came along, it was an advantage. they used it for other puposes too, like gathering other  crops, or planting them, or tending to them, butit was cotton that was the main thing.

answer: an oligarchy is a political system in which the government is run by a group of noble families, or the elite wealthy members of a society. a present day oligarchic government is iran.

explanation:

according to worldatlas.com, the u.s. has an 86% literacy rate.