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

[EX Q]: Tourism is among the _ largest industries in each of the western states.
[EX A]: three

[EX Q]: Climatic regions Contrasts between the interior and the coasts produce _ main climatic regions.
[EX A]: six

[EX Q]: Studies show that one out of _ school-age children walk in their sleep at least once a week.
[EX A]:
ten