Along with the fact that the infrastructural and industrial levels of the African colonies was never really developed by Europeans, the many various and opposing ethnic groups had no one to keep them in check now. As a result many civil wars took place between different religions, specific religious denominations, and specific ethnic groups of said religious denominations. Also nearly all of the leaders that broke free of European rule were woefully unprepared to lead a country both governmentally and economically. All of these factors are what lead to Africa's current problems.
Using the principles of cross-cutting relationships, you can determine the relative age of rocks found in the ground. The idea behind it is that the geologic feature which cuts another is the younger of the two features, and it had been around for 400 years. It's not very precise but it is good for determining relative age.
Decrease pesticide use
<span>develop "cleaner" pesticides
increase organic farming</span>
<span> Northwest Territories, the Yukon, and the Nunavut.
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