I believe the answer is: They are based on the arbitrary borders of old European empires
African continent was colonized by different european empire. To avoid conflicts among the european, they divided africa into several territories and dtermine which country has the jurisdiction over each territories. After African nations gained independence, they still use this separation as borders to differentiate one country with another.
You can search on google it helps
"d. Work that requires a college degree" would be work that becomes more common in a postindustrial society, since there are less jobs in factories.
The long 350 mile body of water that separates the southern portion of United Kingdom from northern France is known as the English Channel.
