11. An espresso machine produces steam for steaming milk in coffee. (a) How much energy is required to change 0.15 kg of water at 25 .C to steam at 100 .C? (b) How much milk at 10 .C can be heated up to 100 .C by 0.15 kg steam at 100 .C? Take c (milk) = 3900 J kg-1 .C-1. 12. Roy prepared 5 kg soyabean milk at 30 .C. To keep it cool, he adds 1.5 kg of ice at -15 .C to the milk. Assume all ice is melted. What will be the final temperature of the mixture? Take c (soyabean milk) = 4000 J kg-1 .C-1