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

Ex Input:
Immune response improves in about _ weeks.

Ex Output:
four


Ex Input:
Pure water contains _ ions and is therefore a nonconductor .

Ex Output:
no


Ex Input:
Weasels have _ toes on each of their paws that are tipped with small, non-retractable claws.

Ex Output:

five