In the case of the B (or center) pillar on four-door sedans, the pillar is typically a closed steel structure welded at the bottom to the car's rocker panel and floorpan, as well as on the top to the roof rail or panel.
On an average a period lasts between 3 to 5 days. It is normal for a girl to have irregular periods in the beginning. During this time, the duration of her periods may vary from as short as 2 days to as long as 7 days. It can take up to a year for periods to become regular.
An average menstrual cycle lasts 28 to 29 days. That's counting from the first day of your period to the day before the next (Fehring et al 2006). Some women have much shorter cycles, lasting only 22 days, and some have much longer ones, lasting up to 36 days. Itâs also common for the length of your cycle to vary from month to month (Fehring et al 2006).