1.____is a kind of 2.____transfer caused by differences in 3.____ and 4.____ of a gas,fluid or molten rocks.Hot fluid materials 5.____because they are 6.____dense,while cold fluid materials 7.____because they are 8.____dense.In the mantle,the repeating rising and sinking of 9.____creates a convection 10.____driving the 11.____plates that ride on 12.____to move slowy and constantly. (choose the correct answer) less,More,Sink,Current,Density, heat,lithospheric,Rise,Convection,Magma, Temperature,Mantle,Asthenosphere,Core,Cycle​