Gravels are the largest particles formed from the breakdown of rocks.
Hope this helps!
dinos were probably around pangea, the movement of land would be my guess lol
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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