Question

How for liquids coefficient of volume expansion is independant of temperature ?
and how bottom of lake or pond start to freeze if water does not have anomalous behaviour?

Answer 1

The question is wrong because the co-efficient of volume expansion for liquids is not independent of temperature.Generally the value of expansion Av=3*Al(3 times the value of the co-efficient of linear expansion).

Ice is a bad conductor of heat.Since, freezing of water occurs by layers,when the top layer is freezed, the heat transfer from water to atmosphere is partially hampered by ice.This anomalous behaviour makes the lakes and ponds support aquatic life even in sub zero temperatures.If water doesnt show the anomalous behaviour, it makes water to freeze as a whole solid just like other liquids .