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.
--------
Question: Aardvarks have ____ toes on the front feet and five toes on their back feet.

Answer: four


Question: Lung disease is America's number ____ killer, responsible for one in seven deaths.

Answer: three


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

Answer:
seven