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: Respiratory therapists complete two to ____ years of education.

Answer: four


Question: Amphibians are the first true vertebrates with ____ limbs.

Answer: four


Question: Infrared energy is recorded in ____ ways.

Answer:
two