The amount of water on earth a. increases slightly over time changes forms. b. decreases slightly over time and does not change form. c. remains the same just in different forms. d. remains the same and does not change form.

B. Decreases slightly over time and does not change form. It's true that water does not change form because it never had a form. If I'm correct lol but it's B. :D

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.