In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.
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Question: Aquatic adults have prominent red reathery gills, are large, and have _ toes on each foot.

Answer: four

Question: Diarrhea is an illness that kills _ and one-half million children per year.

Answer: three

Question: Some botanists recognise _ botanical varieties.

Answer:
two