Seismic wave speeds change with respect to temperature, pressure, and rock composition. how does this information scientists?

Seismic waves travel faster in denser rocks; temperature tends to lower the speed of seismic waves; and pressure tends to increases the speed. Caution: The speed of a seismic wave generally increases with depth, despite the fact that the increase of temperature with depth works to lower the wave velocity.

this helps scientists because it shows how fast a earthquake is moving

Explanation:

i think that c)gold was found there

but i am not sure

there’s no image attached but i can if you want: )