What characteristic of SI prefixes ensures they prevent ambiguity in international documentation?

Answer

They are universal, applying the same factor regardless of the base unit attached.

The prefixes are universal, meaning the prefix for a given factor (e.g., $10^6$ for Mega) is the same whether applied to the metre or the second, preventing ambiguity found in non-metric systems.

What characteristic of SI prefixes ensures they prevent ambiguity in international documentation?
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