Answer:
Small pieces of earth's crust that float on the liquid mantle are called plates.
Step-by-step explanation:
A tectonic plate is a section of the earth's crust and the very top of the mantle, which together are called the lithosphere. The plates are about 100 km thick, and are mainly divided into sima (crust below sea level) and sial (crust below mainland).
Continental plates move constantly, often in opposite directions. Seismic activity occurs in the border areas between each plate, either if the plates separate, in which case cracks and protection volcanoes are formed; or if the plates move against each other, causing strong earthquakes that cause stratovolcanoes and mountain ranges as a result of the collision between the two plates.