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.

Most amphibians reach maturity at three or ____ years.
four

Dogs have to be ____ months old before they are spayed or neutered.
six

Coriolis force is ____ at the equator and increases with latitude to a maximum at the poles.

zero