about 20 inches
The thickness of the Earth's mantle is about 2900 km and it's upper boundary is about 100km deep. There is a really cool cutaway drawing available by using the Wikipedia link.
Continents drift on top of the upper mantle. The core is much further down.
it's 410km to 660km thick
410km
hard rock
about 20 inches
The mantle is found between the core and the innermost layer of the earth. The mantle is made up of mostly solid rock that is 1,802 miles thick.
The lithosphere.
it is the lithosphere
convection currents in the upper mantle
yes it is 2893 kilometers thick
mantle is the thick layer before you reach the core of the earth