It's understandable that scientists know the most about the crust, and less about deeper layers? Why

Which of the following is not a place where hydrogen can be found on earth? a. natural gas well b. atmosphere c. water d. mine

What does the plate tectonic theroy describe?

Which features do all new rocks formed near an oceanic ridge share? check all that apply. pillow-shaped striped pattern provide evidence to seafloor spreading made from molten material iron oriented in same direction