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]: Natural ytterbium is a mixture of ____ stable isotopes, with seven other unstable isotopes known.
[A]: seven


[Q]: Friendship means to trust ____ or more people.
[A]: two


[Q]: Watermelons produce ____ types of flowers.
[A]:
two