It ancient Africa, why did people cross the Sahara desert?

They constantly move around to find new areas to graze their livestock and hunt for food. Trade routes across the Sahara Desert were an important part of the economies of Ancient Africa. Goods such as gold, salt, slaves, cloth, and ivory were transported across the desert using long trains of camels called caravans.

Explanation:

your answer would b. the missisipi river

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