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]: Some botanists recognise ____ botanical varieties.
[A]: two


[Q]: Most bacteria have one or ____ circular chromosomes.
[A]: two


[Q]: Spacecraft starting from the surface of Earth has a ____ initial speed.
[A]:
zero