What does it mean to be "excited" in terms of electron configuration?

It means slangus an electron is the energy level that an electron moves to after absorbing energy. The electron would rather be in its ground state

Organisms are more likely to be more preserved in mud than sand because mud is moist and wet, while sand is very dry.

Sun is explosive itself spread 9 planets.earth is 3rd explosive in the solar system about 500 hundred million years ago . first earth became ice age and freezing climate.centre of earth magma. north zone is artic . south is anatric