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

Input: Consider Input: All loci have _ or two alleles.

Output: one


Input: Consider Input: Metals often crystallize in a _ dimensional version of the hexagonal closest packed structure.

Output: three


Input: Consider Input: Devonian rocks outcrop at less than _ percent of the surface of the United States.


Output: three