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.

Soy products contain ____ known classes of anti-cancer agents, including phytoestrogens.
five

Naiads have ____ caudal filaments and external gills.
two

Brachiopods are marine invertebrates with ____ dissimilar shells.

two