B. Security and national defense
C. Expansion of democracy and human rights
Answer: Africans have a culture that runs deep, which has been around for many years just like the rivers.
Explanation:
The comparison hughes makes between africa heritage and rivers in the negro speaks of rivers is that Africans have a culture that runs deep, which has been around for many years just like the rivers.
Africa's culture is one of the oldest in the world and dates back as the earliest B.C's and most of them are still maintained today despite the pressure from development to do away with them
A = pi * r^2 A = 3.14 * 50^2 A = 7,850 square miles (area of the 50 mile broadcast signal)
A = pi * r^2A = 3.14 * 75^2A = 17,662.5 = 17,663 square miles (area of the 75 mile relayed signal)
Now we just need to subtract the 50 mile signal from the 75 mile signal, so:
17,663 - 7,850 = 9,813 square miles greater
Hope this helps :)
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