Is used when subjects are assigned to different groups through a process of random selection?

How are extrusive rocks formed? magma gets trapped inside earth and cools to rock. volcanoes apply force to solid rocks and eject them. magma gets forced to earth’s surface and cools to rock. volcanoes trap lava inside earth, where it cools to rock.

Other than earth, is also known to have magnetic pole reversal? a: venus b: mars c: earths moon d: the sun

What's the waste product of electrons and pyruvate combining in fermentation?