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.

Pertussis is highly contagious with symptoms that can linger six to ____ weeks.
ten

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

Parliamentary democracy is less than ____ years old in Nigeria.

two