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

Input: Consider Input: Essential oils have a non-toxic, residual effect of up to five months from just _ application.

Output: one

Input: Consider Input: Diatoms are in _ shells and make the water brown.

Output: two

Input: Consider Input: Mellow cheese ages four to _ months and has rich, full flavors with soft to semisoft textures.
Output: seven