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: Human malaria is caused by ____ species of Plasmodium . .

Answer: four


Question: Fibber content increases ____ to four times that of whole wheat bread.

Answer: three


Question: Smokers have ____ times the risk from radon as non smokers.

Answer:
eight