A central idea of “Plate Tectonics: Moving and Shaking” is that geologic activity on Earth happens at tectonic boundaries. Which two sentences support that central idea? “Churning currents in the molten rocks below propel them along like a jumble of conveyor belts in disrepair.”

“The movement of the plates creates three types of tectonic boundaries: convergent, where plates move into one another; divergent, where plates move apart; and transform, where plates move sideways in relation to each other.”

“The tiny Juan de Fuca plate is largely responsible for the volcanoes that dot the Pacific Northwest of the United States.”

“Most geologic activity stems from the interplay where the plates meet or divide.”

“There convergent boundaries also occur where a plate of ocean dives, in a process called subduction, under landmass.”

“Mount Everest, the highest point on Earth, may be a tiny bit taller tomorrow than it is today.”