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]: Numbers can be positive or ____ only.
[A]: zero


[Q]: Elephants give birth to ____ calf every four to nine years on average.
[A]: one


[Q]: Women are ____ times as likely to become depressed as men.
[A]:
three