I think the answer is rills
Answer:
Oil, gas, and minerals
Explanation:
These are the resources common to all three regions.
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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