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

Input: Consider Input: White sturgeon inhabit _ large river systems, all on the western coast of North America.

Output: three


Input: Consider Input: Knives have _ cutting edges for double cutting life.

Output: two


Input: Consider Input: Crickets produce sound by rubbing their _ front wings together.


Output: two