They really help in the process of Africa's state building, creating commercial networks between parts of the continent, and introducing literacy ( especially on northern part of Africa)
They also controlled the sea route between Asia and Africa and managed to maintain the relationship between Africa and the middle east
The NAFTA is going to increase the pollution. This will lower the U.S. environmental standards. This will also cause a huge amount of pollution in Mexico.
A. Buddhism, Confucianism, and daoism
Clouds can cover up the sun, which is the natural source for heat everywhere. When the sun is not in sight, or thickly covered by clouds, this limits the suns radiation and heat waves therefore causing less light and heat.