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.

[Q]: Greed is covetousness, with covetousness being a foundation stone in all of the ____ deadly sins.
[A]: seven


[Q]: Carbon atoms are tetravalent, and therefore, can have ____ bonding pairs around each carbon atom.
[A]: four


[Q]: Female dugongs give birth underwater to a single calf at ____ to seven year period of time.
[A]:
three