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]: Some people routinely sleep only ____ hours a night but feel fine during the day.
[EX A]: four

[EX Q]: All birds have ____ legs with four toes each.
[EX A]: two

[EX Q]: Spatial complexity is varied in ____ different ways.
[EX A]:
three