How were the west african kingdom involved with the slave trade?

https://socratic.org/questions/how-were-the-west-african-kingdoms-involved-in-the-slave-trade

With the development of the trans-Saharan slave trade and the economies of gold in the western Sahel, a number of the major states became organized around the slave trade, including the Ghana Empire, the Mali Empire, and Songhai Empire. However, other communities in West Africa largely resisted the slave trade.

The transatlantic slave trade began during the 15th century when Portugal, and subsequently other European kingdoms, were finally able to expand overseas and reach Africa. The Portuguese first began to kidnap people from the west coast of Africa and to take those they enslaved back to Europe

congress also has implied powers, which derive from the necessary and proper clause of the constitution and permit congress "to make all laws which shall be necessary and proper for carrying into execution the foregoing powers, and all other powers vested by this constitution in the government of the united states.

b. martin luther king jr. wrote and spoke "i have a dream"

explanation:

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