A 7.50 g piece of iron at 100 C is dropped into 25.0g of water at 22.0 C. Assuming that the heat is lost by the iron equals the heat gained by the water, determine the final temperature of the iron/water system. Assume a heat capacity of water 4.18 J g-1 K-1 and iron 0.45 J g-1 K-1.