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]: Mollusks have one or ____ hearts.
[A]: two


[Q]: Gorillas are sexually mature at ____ to nine years of age.
[A]: six


[Q]: Whales are thought to sleep around ____ hours a day.
[A]:
eight