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: World population continues to rise, even as a few countries move toward ____ growth.

A: zero
****
Q: Urine tests are really limited in that they only look for five to ____ substances.

A: nine
****
Q: Eyes turn because of the function of ____ eye muscles.

A:
six
****