Thus 1 cm–3 = 1/cm3 and the units for our densities could be written as gcm3, g/cm3, or g cm–3. In each case the units are read as grams per cubic centimeter, the per indicating division.) We often abbreviate "cm3" as "cc", and 1 cm3 = 1 mL exactly by definition.
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1.9: Density.