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: Gibberellins are diterpenoids derived from four isoprenoid units forming a system of ____ rings.

Answer: four


Question: Heart attacks occur most often around ____ in the morning.

Answer: five


Question: Polyploids are plants with more than ____ sets of chromosomes.

Answer:
two