Cubic kilometre
The cubic metre (in British English and international spelling as used by the International Bureau of Weights and Measures) or cubic meter (in American English) is the SI derived unit of volume. Its SI symbol is m3. It is the volume of a cube with edges one metre in length. An alternative name, which allowed a different usage with metric prefixes, was the stère, still sometimes used for dry measure (for instance, in reference to wood). Another alternative name, no longer widely used, was the kilolitre.
A cubic metre of pure water at the temperature of maximum density (3.98 °C or 39.16 °F) and standard atmospheric pressure (101.325 kPa) has a mass of 1000 kg, or one tonne. At 0 °C (32 °F), the freezing point of water, a cubic metre of water has slightly less mass, 999.972 kilograms.
It is sometimes abbreviated to cu m, m3, M3, m^3, m**3, CBM, cbm when superscript characters or markup cannot be used (e.g. in some typewritten documents and postings in Usenet newsgroups).
Abbreviated CBM and cbm in the freight business and MTQ (or numeric code 49) in international trade.
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