TASK DEFINITION: In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.
PROBLEM: Porcine insulin has _ different amino acid and bovine insulin has three different amino acids.

SOLUTION: one

PROBLEM: Coho usually live for _ years and grow rapidly in their final year.

SOLUTION: three

PROBLEM: White coloring begins to appear when the birds approach _ years of age.

SOLUTION:
four