Which of the following describes what happens as oil is used in an engine? It picks up dirt.
It moves to the top of the crankcase.
It increases friction.
O It produces carbon buildup.

answer:

convection currents in the magma drive plate tectonics. heat generated from the radioactive decay of elements deep in the interior of the earth creates magma (molten rock) in the aesthenosphere. the aesthenosphere (70 ~ 250 km) is part of the mantle, the middle sphere of the earth that extends to 2900 km.