Question

figure 8: a model showing a cross - section of the earth
look at the model shown in figure 8. which of the following pieces of evidence was used by scientists to develop this model showing a hot but solid inner core, a liquid outer core, a solid mantle, and a solid crust?
○ obtaining and examining rock samples by drilling into the earth from the crust to the outer core
○ analyzing the patterns of different rock ages throughout earth using radiometric dating
○ testing the composition of magma immediately after it reaches the earth’s surface
○ analyzing the patterns of seismic waves (p - waves and s - waves)

Explanation:

Scientists cannot drill to the Earth's outer core, so direct rock sampling is impossible. Radiometric dating of rock ages does not reveal the physical state (solid/liquid) of deep layers, and magma at the surface does not represent deep mantle/core composition. Seismic waves (P-waves travel through solids and liquids, S-waves only through solids) allow mapping of the Earth's internal layers and their physical states by analyzing how the waves propagate and refract.

Answer:

Analyzing the patterns of seismic waves (P-waves and S-waves)