Why is the Earth separated into different layers? A. The different masses of each layer cause them to separate and layer. B. The different densities of each layer cause them to separate and layer. C. The different composition of each layer causes them to separate and layer.

D. The different volumes of each layer cause them to separate and layer.

What happens to the temperature within Earth as the pressure increases? A. The temperature remains the same.

B. The temperature decreases and then increases.

C. The temperature increases.

D. The temperature decreases.

Which of the following does not help scientists gather important information about the Earth and its layers?

A. Volcanic eruptions

B. Seismic waves

C. Earthquakes

D. Ocean currents