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A flask filled with ethanol at 20.0 C has a total m of 61.742 g. the flask is emptied and some ball bearings with a m of 21.784 g are added to the flask. The flask is topped off with ethanol and now the total m is 81.604 g. Callculate the density of the ball bearings at 20.0 C. The density of ethanol at this temperature is 0.78945 g/cm3.