In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.
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Question: Climatic regions Contrasts between the interior and the coasts produce _ main climatic regions.

Answer: six


Question: Planaria has rudimentary eyes which produce _ images but detect direction.

Answer: no


Question: Hydrops fetalis results from _ Alpha-chain gene deletions .

Answer:
four