"internal problems unification among Islam in Northern Africa and Western Europe".
It is number 4.......................lol
<span>Sand dunes can encroach on human habitats. Sand dunes move through a few different means, all of them assisted by wind. One way that dunes can move is through saltation, where sand particles skip along the ground like a rock thrown across a pond might skip across the water's surface. When these skipping particles land, they may knock into other particles and cause them to skip as well. With slightly stronger winds, particles collide in mid-air, causing sheet flows. In a major dust storm, dunes may move tens of meters through such sheet flows. And like snow, sand avalanches, falling down the steep slopes of the dunes that face away from the winds, also moving the dunes forward.
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He was a diff. color citizen and he made a speech after rosa parks (diff color) decided to refuse to give up her seat after a long day at work. So he made a " I have a dream" speech and later on he got assassinated in his house.
