1997From which of the following lakes in Africa did the emission of toxic gas lead to the death of a large number of people in 1986?See more
1997One of the the main reasons for the formation Economic Community of West Africa States is to?See more
1997An agricultural practice where water has to be artificially provided during the rainy season is known asSee more
1997The processes by which materials are physically transferred from one soil layer to another is calledSee more
1997The most important environmental resource that sustains natural processes in an ecosystem isSee more