OK, my teacher set me this question in preparation for my exams, but I was ill when he taught this topic back in November, so I don't really know how to go about answering it. I've tried conducting some research on the web but it hasn't really gotten me any further. Suppose that water at room temperature of 28°C is put into an ideal refrigerator that maintains an inside temperature of -3°C. The specific heats of water and ice are, respectively, 4187 J/(kg·C°) and 2090 J/(kg·C°); the latent heat of fusion for water is 3.34x105 J/kg. a) What is the cost of making 96 lb (43.2 kg) of ice if electricity costs $0.10 per kilowatt-hour? b) What percentage of this cost goes into chilling the water from 28°C to 0°C (without freezing it)? c) What percentage of the total cost goes into freezing this chilled water but not cooling the ice that forms? d) What percentage of the total cost goes into cooling the ice that forms to -3°C? So could somebody point me in the right direction please? He's given me only 14 more hours to answer it!