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

[Q]: Tapirs have hoofed toes, with four toes on the front feet and _ toes on the hind feet.
[A]: three


[Q]: Tarantulas have _ pairs of book lungs.
[A]: two


[Q]: Melanocytes are dendritic and are distributed roughly _ per six basal cells.
[A]:
one