In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.

[Q]: Rodents have _ toes on their front feet and five on the hind feet.
[A]: four


[Q]: Sea urchins have _ paired rows of tiny tube feet which are found amongst the spines.
[A]: five


[Q]: Asbestos fibers can be as little as _ micrometers wide.
[A]:
three