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

Input: Consider Input: Tobacco kills four million people a year, one death every _ seconds.

Output: eight

Input: Consider Input: Pangolins walk on all _ of their stout limbs, which are adapted for digging.

Output: four

Input: Consider Input: Resident lionfish occupy _ separate coral heads.
Output: two