Geologists can use Seismic waves to learn about Earth’s interior. P waves travel faster than S waves. S waves travel through solids only, which tells geologists that the Earth's core is liquid. Geologists call the outer, solid area of Earth the crust; the next layer is the Mantle. Finally, at the very center, is the core.
<u>Explanation:</u>
Researchers can comprehend Earth's inside by contemplating seismic waves. These are floods of vitality that moves through Earth and they move correspondingly to different sorts of waves, similar to sound waves, light waves, and water waves.
The earth is made up of three layers namely Crust (the outer layer) is solid, mantle (the middle layer) which is liquid and core (inner layer) which is very hot. Thus the correct answer for the blanks given in the passage is: Seismic waves, Earth and Mantle.