A piece of jewelry made of gold weighs 8.56and has a volume of 8.56g and a volume of 0.485cm3. Gold has a density of 19.3g/cm3 and copper has a density 8.96g/cm3 calculate the precentage by mass of each metal in the jewelry. Assume the total volume
of the jewelry is the sum of the volumes of the 2 metals it contains