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

[Q]: Cockroaches require food every _ to ten days but mut take in water every ten days.
[A]: seven


[Q]: Metals often crystallize in a _ dimensional version of the hexagonal closest packed structure.
[A]: three


[Q]: Fledglings stay with the adults about _ weeks.
[A]:
four