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.

Human gestation is divided into three trimesters of ____ months each.
three

Teething begins for most babies around ____ to six months.
four

Pups stay in the den for about ____ weeks and then begin traveling short distances with adults.

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
six

