What are liters, millimeters, and cubic centimeters used to measure

They are all units of volume as are, Cubic Metres, Cubic Inches and Cubic Feet. 1mL and 1 cubic centimetre (cc) are the same. Any one of the above is used to indicate the Density of substances which are compared to the density of pure water. By multiplying the Density of water by the Specific Gravity of the substance (Liquid or Solid), its density and, by calculation, it mass can be found. (cc and cmÂł are used for the solid materials. (a mL or Litre of copper or other solid doesn't quite sound right as they are used for liquid volume.