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

Example Input: Jurassic rocks have _ outcrops in the area but they are identified by bore holes.
Example Output: no

Example Input: Some manatees have _ or four nails on the tip of each flipper.
Example Output: three

Example Input: Most bats return to their roosts by _ or five o'clock in the morning.
Example Output:
four