How did the African slave trade devastate the continent over the centuries ? Who participated in the slave trade? (1-2 sentences needed)

there are two main types of historical sources: primary sources and secondary sources. a primary source is something that originates from the past. it can be a chronicle, a piece of pottery, or even a piece of glacial ice that gives us climate data about the levels of atmospheric carbon one thousand years ago.

i think that the answer is polishing peanuts