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

[EX Q]: Tin exists in _ allotropic forms.
[EX A]: three

[EX Q]: Cubs emerge from the den when they are four to _ months old.
[EX A]: six

[EX Q]: Lines of force are _ dimensional, surrounding a bar magnet on all sides.
[EX A]:
three