1. The problem statement, all variables and given/known data The same question was asked on this forum about two years ago, however I did not find any of the given answers clear. The question was the following: A small pond has a layer of ice 1cm thick floating on its surface. The air temperature is -10C. (a) What is the temperature of the liquid water just below the ice? (b) Write the expression for the rate of heat transfer through the ice as a function of thickness of the ice? (c) Write the expression for the rate of heat flow required to freeze the water? Hint: first find how much heat must be removed to freeze a given thickness of ice. (d) Find the rate in cm/hr at which ice is added to the layer. (e) How long does it take for a 20cm layer to build up? 2. Relevant equations H = dQ/dt = kA(TH - TC)/L 3. The attempt at a solution for part b, I attempted to derive H with respect to L, and got the following: dH/dL = -kA(TH - TC)/L2 I am not sure if I am misunderstanding what the question wants from me, and would appreciate any guidance anyone provides.