How long mail takes is going to depend on many factors along the way. Many factors, indeed, though with regard to how long does priority mail take, the answer is, not long. In fact, the United States Postal Service says your package or envelope will arrive within two days.
Both the 2009 IRC and the DCA6-09 allow #2 southern pine 2x10s to span 13 feet 1 inch at 24 inches on-center at a design load of 50 psf. That means these joists can span the 12-foot depth of the deck, and the beam can be located at the perimeter. Nine joists will be needed for the 16-foot width.
A 2x4 stud with the same loading as above but spaced only at 16 inches does not calc. Shorten that stud to 8 feet long and it makes it, but barely. To get a 2x4 to calc at 24-inch spacing, it can be no longer than 9 feet and support only roof load. Most of the trouble with 2x4 studs is their weakness in resisting wind load. But interiors donât experience wind, so using 2x4s at 24-inches there makes sense.