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An attometer is a unit of length, a combination of the metric prefix atto (symbol a) and the SI unit of length meter (symbol m), equal to 10−18 meter or 1.0E-18 meter and its symbol is am. Plural name is attometers.
A league is a unit of length (or, in various regions, area). It was common in Europe and Latin America, but is no longer an official unit in any nation. The word originally meant the distance a person could walk in an hour. Since the Middle Ages, many values have been specified in several countries.