Answer:
A fraction with value 1 that we use to convert quantities.
Explanation:
1 micro = 0.001 milli 1 milli = 1000 micro
The prefix milli-, likewise, may be added to metre to indicate division by one thousand; one millimetre is equal to one thousandth of a metre. Decimal multiplicative prefixes have been a feature of all forms of the metric system, with six dating back to the system's introduction in the 1790s.