Question

FIRST ONE WHO ANSWERS THIS QUESTIN WILLLL BEEE MARKED BRAINLIEST.

Answer 1

they use the waves that are formed to see and learn about the different layers there are in Earth's crust

Answer 2

The answer to this question is

"Scientists can tell by observing the seismic waves that are recorded all over the surface of the earth from distant earthquakes. The seismic waves are reflected (bounced off) layers of different density, and they are refracted (bent) when they enter layers of different density."