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.

[EX Q]: Sapsuckers are a group of ____ species known for literally drinking the sap of trees.
[EX A]: four

[EX Q]: Most dens are oval shape, six to ____ feet long and about six feet in height and width.
[EX A]: nine

[EX Q]: Indoor air is ____ times more polluted than out door air.
[EX A]:
three