The United States is one of the few countries that officially uses both the metric and customary system of measurement. Myanmar uses a combination of both systems as well.
Some countries in Africa used the customary legal system. They usually use a combination of a customary system and a civil code.
The UK uses the predecessor to US Customary called 'Imperial' - most of which is identical apart from volume measures.
Officially, three do: Myanmar, Liberia, and the USA.
There is exactly 2 the metric system and the customary system
44.34375 ml in 3 Tbs
Piecemeal, over centuries and from across many countries - although the UK had a disproportionate share of units.
All of them. Whatever units a country uses are 'customary' in that country.
In many countries, a kilometer is a common unit of measurement for distance. It is equivalent to 1000 meters or about 0.62 miles.
Only the U.S.A. uses the customary system. Myanmar(Burma) and Liberia both use the old UK Imperial system, which uses the same names for units as the customary, but assigns them different sizes. The whole of the rest of the world uses metric.
Not everybody will eat meat with wine. In many European countries it is customary to drink red wine with meat but this is not essential.
3 Significant figues are any other number apart from 0