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: Gorillas are sexually mature at ____ to nine years of age.

Answer: six


Question: Food waste is transformed into soil-like humus in three to ____ days.

Answer: seven


Question: Autotrophic organisms can use all ____ forms.

Answer:
three