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

[EX Q]: Pollination is accomplished only by insect-agency, and where insects fail _ fruits are ripened.
[EX A]: no

[EX Q]: Reds mature well for six to _ years.
[EX A]: eight

[EX Q]: Sexual maturity is reached at about _ to five years of age.
[EX A]:
three