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.

Plants have roots for ____ main reasons.
two

Sexual maturity occurs at ____ to four years for females and four to five years for males.
three

Alkaline batteries last ____ to eight times as long as zinc-carbon cells, their predecessors.

five