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.

[Q]: Sexual maturity is reached at ____ years, and females calve every other year.
[A]: four


[Q]: Owls have ____ toes on each foot, like most birds.
[A]: four


[Q]: Problem solving, information integration, and analysis are ____ kinds of thinking.
[A]:
three