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

[EX Q]: Prostate cancer has _ symptoms in the early stages.
[EX A]: no

[EX Q]: Anemone has _ vents.
[EX A]: two

[EX Q]: Men live on average about _ years less than women in most developed countries.
[EX A]:
seven