the mantle and core are composed of different material
P waves refract as they travel through Earth. The shadow zone exists because of seismic waves. The shadows show when the earth spins around.
compass magnets can be deflected by earths magnetic field or other permanent magnets
Bahrain receives the least amount of rainfall annually with 77 mm of rain.
dissolved oxygen is dissolved oxygen
Samples of Earth's crust contain less iron than found in meteorites, and iron is a comparatively heavy element that would have sunk into the planet when it was being formed.
Sadly they ARE extinct in the WILD.
The ecosystem becomes more stable and diverse.
Taiga
A conditional statement.
At ocean ridges
magnetic stuff...