Suppose a lake has a layer of ice 12 cm thick on its surface. the top of the ice layer is cooled by the atmosphere to -4.75° c. the lower surface is in contact with water at 0.0° c. the thermal conductivity of ice is 0.004 cal/(s · cm · c°). (a) at what rate is heat transferred through a 1.2 cm2 area of the ice? answer 1 0.0019 correct cal/s (b) how long will it take to freeze an additional 1.2 mm of ice onto the lower surface of the ice?