Answer: The answer is Core Samples, Earthquakes, S waves, and Rock composition.
Step-by-step explanation:
It’s talking about study the whole interior of Earth not just one part el to learn about the Earth they have to study the rocks. The waves allow us to know whether or not the the outer core is liquid I believe. The Earthquakes shake the Earth allowing us to get new rocks. Rock composition helps us to be able to know what our old Earth was like and when they were deposited. And Core samples allow to be able to see the temperature of the core and such things.