You need at least 3. seismic stations provide only a circle around the station. so from geometry 3 circles intersect in a point. that is why you need 3 stations
Two ecozones would be different it they had two different climates
1 to C, 2 to E, 3 to A, 4 to B, 5 to D
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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