Q #1: Oceanic crust is usually more active than continental. They also differ in thickness, density, age, and chemical composition.
Q #2: Hot fluid material that resides within the earth's crust from which lava and other igneous rocks are developed. Q #3: Folded mountains are formed when two tectonic plates move together. This special movement of the two plates compels sedimentary rocks upwards, which results in folds.
