Given a sentence, fill out the missing word with a 'no' or a number (between zero and ten). You should write the numbers with english alphabet, like: four instead of 4.
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Question: Environmentalists warn that ____ turtle species are in severe decline from over-exploitation.

Answer: six


Question: Some airports have ____ parallel runways.

Answer: two


Question: Zygospores result from the fusion of ____ similar hyphal elements.

Answer:
two