Answer:
Scientists use waves to study the different layers of the earth. Usually, they use seismic waves, which are waves generated by earthquakes or nuclear-test explosions. ... So, scientists study the path and speed of these waves through the earth to decipher boundaries and the materials that make up the layers.
Step-by-step explanation:
I don't know if this answers your question but I don't think what you asked was grammatically correct but I hope this helps in some way.