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

Q: Birds begin dying of fowl cholera _ to nine days after exposed to the virus.

A: four
****
Q: Weasels reaching _ to six years are regarded as fully mature.

A: five
****
Q: Mayflies emerge as adults, mate, and lay their eggs in the space of about _ days.

A:
three
****