I believe they are called Energy Levels or Energy Orbitals.
Comets are usually formed of ice and other suave debris, while asteroids typically contain metals.
A) At 0 C water forms ice but as mentioned above F) water's greatest density occurs at 4 C and it decreases below 4 C so ice is lighter than 4C water, thus, at 0C ice comes to surface and acts as insulator thereby preventing lower water from freezing.
