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

[EX Q]: Butterflies have _ pair of legs - each divided into five parts.
[EX A]: three

[EX Q]: Atoms are most stable when they have _ electrons in their outer electron energy level.
[EX A]: eight

[EX Q]: Dentary teeth have about _ denticles and weak ridges.
[EX A]:
eight