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

Ex Input:
Phosphates are made of _ phosphorus atom surrounded by four oxygen atoms.

Ex Output:
one

Ex Input:
Induction also operates early in development, even before the _ layered embryo forms.

Ex Output:
three

Ex Input:
Process color is used to reproduce color photographs or pages using more than _ different colors.

Ex Output:
four