I am absolutely sure that <span>the percent of the Sahara Desert is covered by sand sheets and dunes is definitely 25 %. Even though it might seem weird, it is actually correct and here are the pic from artcicle about Sahara which will pose as a proof : )
Do hope it will help!
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Answer:
<em>The focus is the place inside Earth's crust where an earthquake originates. The point on the Earth's surface directly above the focus is the epicenter.</em>
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Tectonic landform, any of the relief features that are produced chiefly by uplift or subsidence of the Earth’s crust or by upward magmatic movements. They include mountains, plateaus, and rift valleys.