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

[Q]: Tobacco kills four million people a year, one death every _ seconds.
[A]: eight

[Q]: Most cats have only _ to five toes per paw, depending on whether it is the front or back paw.
[A]: four

[Q]: Trees are a _ year crop.
[A]:
ten