The density of gold is 19.3 g/mL, that of lead is 11.4 g/mL, that of iron 7.8 g/mL, and that of aluminum 2.7 g/mL. A student is given separate samples of three substances A, B, and C, along with a graduated cylinder containing 50.0 mL of water. Each sample has a mass of 200.0 g, and the student finds that the volumes of the samples are A, 25.64 mL; B, 10.36 mL; and C, 17.54 mL. What is the identity of each substance?