The systemic circulation is the portion of the circulatory system is the network of veins, arteries and blood vessels that transports blood from heart, services the body's cells and then re-enters the heart, the Mayo Clinic noted. [Image Gallery: The BioDigital Human]
A southern pine (2) 2x12 beam can span 8 feet when supporting joists spanning a maximum of 14 feet, and it can cantilever 2 feet beyond the posts on each side. With the allowable cantilever of the joists, this beam would support a deck 12 feet by 17 1/2 feet.
This on-line span calculator will size floor and deck joists and roof rafters for most conditions. A very good Span Calculator from the American Wood Council. Open this link in another window and then follow the directions below to learn how to use it. = length divided by a number. The larger the bottom number the stiffer the member will be. If you set a floor joist to L/360 (a common value) it will be allowed to deflect (bow or bounce) a maximum of 1 for every 360 (30') of span.