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.

Infected rodents carry and secrete the virus for about ____ days.
seven

Pigs grow very quickly and are normally ready for sale at ____ to six months of age.
four

Many scientists believe the neutrino has ____ mass at all.

no