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

[EX Q]: Cormorants are monogamous and breed in colonies of up to _ thousand pairs.
[EX A]: three

[EX Q]: Pelycosaurs are a paraphyletic group of _ primitive families of synapsids.
[EX A]: six

[EX Q]: Roaches can live without food for up to _ weeks.
[EX A]:
six