An unknown metal of mass 512 g, at a temperature of 15 °c, is dropped into 325 g of water held in a 100-g aluminum container at a temperature of 98 °c. if the system reaches thermal equilibrium at 78 °c determine the specific heat of the unknown metal. note: t(k) = t(c) +273. the specific heat of aluminum 900 j/kg/k. the specific heat of water = 4190 j/kg/k (a) 485 j/kg/k (b) 900 j/kg/k (c) 1800 j/kg/k (d) 655 j/kg/k