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]: All matter exists in ____ dimensional space, both internal and external.
[A]: three


[Q]: Birds have ____ basic types of feathers.
[A]: three


[Q]: Goats are ____ legged animals.
[A]:
four