Question $6(20$ points$)$

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Beam Design $2/4$: Picking a Beam Size

A wood floor beam has a uniformly distributed dead load of $80$ pounds per foot and a live load of less than $7$ days' duration of $80$ pounds per foot on a span of $22$ feet.

What size beam should be used, considering bending stress only, using No$.1$ and better Douglas fir and assuming that the weight of the beam is included in the dead load? $($ do not increase the allowable stress by $1\mathrm{.}25$ as that is only applicable for roof beams. This is a floor beam$)$

$414$

$48$

$410$

$412$