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: Carbon atoms are tetravalent, and therefore, can have ____ bonding pairs around each carbon atom.

A: four
****
Q: Calves are spotted when born and develop their brown coats in ____ months.

A: six
****
Q: Plant roots absorb ____ vital nutrients.

A:
three
****