Answering from technical documentation
The commonest failure is not a wrong answer. It is a right answer from a superseded revision.
Always state
The document, its revision, and its date. Then the answer, quoted. A specification without its revision is unusable on the shop floor.
Check the revision applies
The part being worked on may have been built to an earlier revision. Ask which serial or batch, and answer against the revision that applies to it — not against the latest.
Tolerances and units
Quote tolerances exactly as written, with the units and the datum. Never convert silently; if a conversion is needed, give both and say which is the controlled one.
When documents conflict
Name both, with revisions, and stop. The drawing usually governs over the manual, but saying so is engineering's call.
Never
Answer from an uncontrolled copy, round a tolerance, or infer a dimension from a drawing that is marked not to scale.