Seismic waves traveling through the earth<span> refract for the same reason that light refracts when entering different substances (e.g. air, water). The inner </span>core<span>has a different density from the outer </span>core<span>, and this difference in density </span>tells<span> us that it is </span>solid<span>.
Hope this helped. Good luck!
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Well, if you mean layers of the earth than the 1st one would be crust the second would be the mantle and the third would be the outer core.
Answer: Sedimentary rock
Explanation:
From google (There are three main types of rock: igneous rock, metamorphic rock, and sedimentary rock. Almost all fossils are preserved in sedimentary rock. Organisms that live in topographically low places (such as lakes or ocean basins) have the best chance of being preserved.)
The answer is: convection of the core
