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

Example Input: Diarrhea is an illness that kills _ and one-half million children per year.
Example Output: three

Example Input: Young groundhogs are weaned and ready to seek their own dens at _ to six weeks of age.
Example Output: five

Example Input: Physical hunger is a physiological process that occurs every three to _ hours.
Example Output:
four