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

[Q]: Hoatzin has typical foot with _ toes forwards and one backwards.
[A]: three


[Q]: Corms are undifferentiated, uniform, and contain _ rings when cut apart.
[A]: no


[Q]: All teeth have the same general structure and consist of _ layers.
[A]:
three