<span> The flooding brought fresh silt to farmlands, leaving them ready to plant. Egypt had a very strong agricultural economy
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Because it challenged what people thought was true at the time and it scared them. Those in authority at the time wanted to silence anyone that supported change. A prime example of this was the persecution of Gelileo because he supported the idea of the Heliocentric Theory, or the theory that the sun is the center of the solar system rather than the Earth being the center.
Barack Obama is the president of eeuu
Germanic tribes, Visigoths
I believe it's "Laffer Curve".