Dimensions and Units 'mm' means millimetre 'cm' means centimetre 'm' means metre 'km' means kilometre 'mm²' means square millimetre 'cm²' means square centimetre 'cm³' means cubic centimetre 'm²' means square metre 'ha' means hectare or 10,000square metres 'l' means litre 'cc' means cubic centimetre 'm³' means cubic metre 'g' means gram 'mg' means milligram 'kg' means kilogram 'tonne' means 1,000 kilograms 'N' means Newton 'kN' means kilo Newton 'kcal' means kilocalorie 'h' means hour 'l/s' means litre per second 'm³/s' means cubic metre per second 'kg/cm²' means kilogram per square centimetre 'kg/m³' means kilogram per cubic metre 'C °' means degrees Celsius '%' means per cent 'ë' means per thousand.