Question

(1) Earth's crust is made up of relatively rigid plates that ride atop Earth's hot, semiliquid mantle. (2) The plates are called tectonic because they're in constant motion. (3) They can move because Earth's mantle is a very hot and semiliquid fluid called magma. (4) Volcanoes are a result of magma rising up or erupting through a plate, particularly where plate boundaries are moving against each other. (5) Also, when plates slide against each other, causing friction along adjacent plate boundaries, earthquakes frequently occur. (6) Therefore, we often find volcanoes and earthquakes along plate