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

Example Input: Echocardiography demonstrates in clear, graphic fashion the _ cardiac chambers and four valves.
Example Output: four

Example Input: Cockroaches require food every _ to ten days but mut take in water every ten days.
Example Output: seven

Example Input: Lions reach full maturity at around _ years of age.
Example Output:
six