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Units

Metre

Also Known As Meter

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The metre is the base unit of length in the International System of Units. Since 2019 it has been defined by fixing the speed of light at exactly 299,792,458 metres per second, so the metre is the distance light travels in a vacuum in 1/299,792,458 of a second, tying length directly to the definition of the second and a fixed constant of nature rather than to any physical object.

Facts
SymbolSourced to the subject's own account
1
Sources
1. International System of Units (Wikipedia)
WikipediaLede
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US English uses the spelling deka-, meter, and liter, and International English uses deca-, metre, and litre.
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