|
|
|
|
|
|
The are (/ˈɑːr/ or /ˈɛər/) is a unit of area, equal to 100 square metres (10 m × 10 m), used for measuring land area. It was defined by older forms of the metric system, but is now outside of the modern International System of Units (SI).
A millibarn (symbol: mb) is a unit of area equal to 10−31 m2.