Write an inquisitive question about a specific text span in a given sentence such that the answer is not in the text.

Sentence: Yet whether in a direct or supporting role , aircraft carriers have taken part in almost every U . S . major military operation since World War II .<sep>Span: in almost every U . S . major military operation
Have there been exceptions?

Sentence: Such products are made possible by recent advances in technology that allow manufacturers to create nano - sized silver and incorporate it into various materials .<sep>Span: nano - sized
What unit of measure determines this?

Sentence: " We ' re seeing what appears to be a new geological phenomenon , " she said .<sep>Span: new geological
What distinquishes this as something that is new?