Which of the following is a major environmental problem in heavily industrialized regions?

In Nigeria, hydroelectric and thermal energies are generated respectively in

An example of a horst in Africa is

Power for aluminium smelting is one of the principal objectives of the hydro-electric project in

The two dams found in the Upper and Lower Nile respectively are

The group of countries that produce most of the cocoa in West Africa is

Oil refineries are found in which of the following sets of states?

On the Jos plateau, tin and columbite are obtained mainly from

An African port that handles more of other countries products than its own is