In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.

[Q]: Smokers die an average of six to _ years earlier than nonsmokers.
[A]: eight


[Q]: Dashes are _ times the length of dots.
[A]: three


[Q]: Printing presses use a minimum of _ ink colours to accurately reproduce 'full colour' images.
[A]:
four