The April 3 letter “Questions that need answering” asked why the DMV issues two license plates when you only have to display one.

At ocean-ocean convergences, one plate usually dives beneath the other ... Earth's mantle rises toward the surface and pushes apart two or more plates. Mountains and volcanoes rise along the ...

They're less common than they used to be, but you can still see some semi-trucks sporting more than one license plate. Why?

a convergent boundary occurs where one plate slides under another as the two are pushed together. If there is land at the edge of one of these plates, the ocean plate will subduct, or slide under ...

Constructive plate margins close constructive plate marginAn area where two tectonic plates are moving away from one another. are where tectonic plates pull apart due to convection currents in the ...