Why does the bottom of a lake not freeze insevere winter though the su

1.	Why does the bottom of a lake not freeze insevere winter though the surface is all frozen?
Answer» The ice formed on the surface is less DENSE than WATER and floats at the water surface. This layer acts as an insulation layer which PREVENTS contact between the water bulk and the freezing SURROUNDING, THUS preventing further freezing of water.Explanation:

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