Do most menstrual periods last between 2 and 12 days.

The person who utilize the progression principle will keep adding the difficulty of the exercise that he's doing, while the person who does not, will only stay stagnant.  the person that utilize progression principle, will get a stronger endurance because now his body is conditioned to do harsher routines.{the answer was already on verified)

Blood transfusions were rarely done and often fatal; they were outlawed until the nineteenth century.

Starvation is bad because it makes your body unhealthy. if you don’t have a healthy diet you can age faster or even die before you’re 30.

So that you don't get baby's but also prevents stis such as hiv