Question 18 (1 point) saved when an oceanic plate collides with another oceanic plate, the called subduction , which is • plates pile on top of each other, forming mid-ocean ridges older, colder plate goes beneath the younger. warmer plate younger. warmer plate dives beneath the older. colder plate both plates disappear downward

Mantle convection is the process that drives plate tectonics. the theory of plate tectonics states that the crust is divided into plates that float on the semi molten mantle below. the circular motion of the magma as it slowly rises and falls or move though convection cells drags the plates along causing them to move. the heat source in the lamp would represent the earth's core. the core is the source of energy that drives convection in the mantle. the lava represents molten magma under the earth's surface. if the lava lamp had floating pieces they would move as the circular motion of the lava in the lamp as it rises and falls would move them along the surface. these floating pieces would represent pieces of the earth's crust. 

Intrusion is the best answer and the newest form.

Considering only personal water use, people in the developed world use about  germany was the only country in world war 1 to use u-boats  than people in the developing world