Crust, mantle, outer core, inner core
Mantle, crust, outer core, inner core
Inner core, outer core, mantle, crust
Continental cruse, oceanic crust, mantle, core
Two or more rocks
Two or more elements
Two or more atoms
Two or more molecules
Not that bright
Closely compacted together
None of the above
By digging down directly to it.
By studying rocks.
By observing the Earth's surface
By studying the ocean floor.
It is 67% of the Earth's mass
It is about 3,00 km thick
It is less than 1% of the Earth's mass
It includes 3 different types
Here's an interesting quiz for you.