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Find the center of mass of a 60-cm long rod, made of 30 cm of iron (density 8.6 g/cm3) and 30 cm of aluminum (density 2.6 g/cm3). Express the location of the center of mass as measured from the left of the rod, assuming that the iron part of the rod is on the left and the aluminum part is on the right. $0M : 21.96 0\" 21.96 cm from the left of the bar