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

Q: Rainforests cover less than _ percent of the Earth's surface.

A: two
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Q: Aquatic adults have prominent red reathery gills, are large, and have _ toes on each foot.

A: four
****
Q: Flamingos belong to the genus phoenicopterus, and there are _ different species of flamingos.

A:
six
****