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what does micro prefix mean in the metric system
Micro- (Greek letter μ or legacy micro symbol µ) is a unit prefix in the metric system denoting a factor of 10−6 (one millionth).
can you tell me about the greek letter for the prefix micro
The symbol for the prefix comes from the Greek letter μ (mu). It is the only SI prefix which uses a character not from the Latin alphabet.

Question: when was the prefix confirmed
Self-contained rewrite: when was the prefix micro confirmed