A XY kg block of iron casting at 450 K is thrown into a large lake that is at a temperature of 200 K. The iron block eventually reaches thermal equilibrium with the lake water. Assuming an average specific heat of 0.50 kJ/kg. K for the iron, determine (a) the entropy change of the iron block, (b) the entropy change of the lake water, and (c) the entropy generated during this process.