Answer:
Milli, m.
Step-by-step explanation:
Hey there!
In this case, according to the given information, it turns out possible for us to answer to this question by bearing to mind the attached file whereas the most common prefixes and their factors are shown both in standard and scientific notation.
In such a way, we will be able to infer that the prefix related to the numerical value of 0.001 is milli, m, for example 1 mm which is 0.001 m.
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