Given a sentence, fill out the missing word with a 'no' or a number (between zero and ten). You should write the numbers with english alphabet, like: four instead of 4.

[EX Q]: Statistics show that one out of every ____ people has a mental illness.
[EX A]: four

[EX Q]: Nymphs are less than ____ millimeters in size.
[EX A]: two

[EX Q]: Gerbils usually live to be about ____ years old.
[EX A]:
three