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

Input: Consider Input: New species are believed to arrive in the Mediterranean at the rate of _ to five annually.

Output: four

Input: Consider Input: Intramural football consists of _ leagues.

Output: three

Input: Consider Input: Cleavage is perfect in _ directions, forming rhombohedrons.
Output: three