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

Ex Input:
Gestation is _ to nine months long, after which a single calf is born.

Ex Output:
eight


Ex Input:
Disruptive selection can lead to _ new species.

Ex Output:
two


Ex Input:
Blood is pumped through vessels by _ pairs of aortic arches, or hearts.

Ex Output:

five