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]: Prions are protein molecules which have ____ metastable states.
[A]: two


[Q]: Humans grow with ____ sets of teeth.
[A]: two


[Q]: Red squirrels can live for up to ____ years.
[A]:
six