esign a wood beam using $4\text{'}\text{'}$ dimensional lumber $($the width of

the sec$$on is set as b $=4\text{'}\text{'},$ and you need to select the depth d of the sec$$on$)$ to carry a uniform

distributed load of $250$ plf over a L $=12\text{'}$ span. The lumber is No$.2$ southern yellow pine $($SYP$),$

where $=1,100$ psi, $=80$ psi, and E $=1\mathrm{.}6\backslash$times $106$ psi, adequately glued, screwed, and bolted. The

deflec$$on requirement is D $<$ L$/480.$ You should consider the beam$$s self$-$weight