International trade, they are one of the biggest trade countries in the world so that makes sense:)
Answer:
it is banned in other countries too
Explanation:
Explanation:
The development of such major Sudanic kingdoms and empires as Ghana, Mali, Songhai, the Hausa states, and Kanem-Bornu along the southern fringes of the Sahara had a number of important consequences for the history of western Africa as a whole