Question

water at depth in lake stays cold even on hot summer days how

Answer 1

water at depth in lake stays cold even on hot summer days because, the sun rays of the sun are reflected through the surface of water and some amount of sun rays can reach at specific distance in water. after this specific depth, the sun rays cannot reach and hence the temperature is less there.

Answer 2

because the heat of sun doesnot reach to the deapth of water.

and also because of the heavy water in it