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: Seismologists offer ____ major theories for the occurrence of large, deep earthquakes.

Answer: three


Question: Intermittent streams flow at least ____ months of the year.

Answer: six


Question: Crustaceans have complicated life cycles sometimes involving ____ separate metamorphoses.

Answer:
four