What are the earths layers?

What is the size of the crust?

What state is the Mantle?

What is the size of the core?

What is a tectonic plate?

What is the rate that the plates move?

What was Alfred Wegener's Theory in 1915?

What did his theory suggest?

What was the evidence that he used?

What was the main reason that scientists found his theory so hard to believe?

How did the continents actually move?

What is the thing called that pushed the tectonic plates over the surface of the Earth?

What happens at boundaries between tectonic plates?

Why can these events never be accurately predicted?