How were the west african trading empires able to grow and become wealthy?

At a continent-continent convergence,

Air masses are characterized by various properties including temperature humidity air temperature pressure and wind speed . which of the following air masses is associated with low relative humidity and high temperature

Why did the belgian parliament pass laws to decentralize its government? a. to increase trade with neighboring luxembourg b. to decrease the political power enjoyed by the flemish c. to enable belgium to join the european union d. to reduce tensions between belgium's two main ethnic groups