The surface layer of the water freezes solid creating a barrier that insulates the ice below so that it keeps a steady temperature usually a few degrees above freezing (32 degrees).
Answer:
adjective
adjective: Greek
relating to Greece, its people, or their language.
noun
noun: Greek; plural noun: Greeks
1.
a native or inhabitant of modern Greece, or a person of Greek descent.
a Greek-speaking person in the ancient world, especially a native of one of the city states of Greece and the eastern Mediterranean.
2.
the ancient or modern language of Greece, the only representative of the Hellenic branch of the Indo-European family.
3.
US
a member of a fraternity or sorority having a Greek-letter name
The correct answer is biological anthropology, or physical anthropology.
It is centered around human beings only, with respect to their common or different features that they either share or don't share with their related non-human primates and other ancestors. It deals with human evolution, the study of their behavior, reproduction, etc.
Astronomers have seen stars forming within a nebular cloud. As the nebular cloud condenses and its own gravitational attraction collapses it, heat and energy build up creating a planet.