What statements are true of a white dwarf?

A white dwarf is the remnant of a star that has exhausted its nuclear fuel and has shed its outer layers, leaving behind a hot, dense core primarily composed of carbon and oxygen. It is supported against gravitational collapse by electron degeneracy pressure. White dwarfs have a high density and are typically about the size of Earth, yet they can contain mass comparable to that of the Sun. Over time, they gradually cool and fade, eventually becoming cold, dark "black dwarfs," although the universe is not old enough for any black dwarfs to exist yet.