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

[Q]: Prolactin exists in _ heterogenic forms which possess varying biological activity.
[A]: three


[Q]: Most cats have only four to _ toes per paw, depending on whether it is the front or back paw.
[A]: five


[Q]: External radiation is given in divided doses to the pelvis _ days a week for five weeks.
[A]:
five