There is no such thing as a "metric unit" for a door. If you mean measurement, you would use either metres (m), decimetres (dm), centimetres (cm), or millimetres (mm). There are 10mm in 1cm, 10cm in 1dm, and 10dm in 1m. Metres converted to the smaller units are as follows: 1000mm, 100cm, and 10dm. Some examples of door measurements in the different units are 1.9m, 19dm, 190cm, and 1900mm (dm is the least used of these four, cm and m the most common, and mm are usually only used on small objects).
I would use the metric unit is inches
That one!
You best bet would probably be to use kilograms.
The gram.
Centimetre
You would use square metres (m2) to find the area of a door.
I would use the metric unit is inches
That one!
sqaure meters
You best bet would probably be to use kilograms.
Grams.
Kilogram
a millimeter
Millimeter
The kilogram.
Millimetres
Millimetres.