Problem $1.$ An aluminum alloy $[E=10,300$ksi tee$-$shaped bar is used as a beam. The cross section of the tee shape, shown in Figure P$8\mathrm{.}9,$ has a total depth of $d=7\mathrm{.}5in.$ The centroidal $z$ axis of this cross section is located $2\mathrm{.}36$ in $.$ above point $H.$ The beam spans in the $x$ direction and it bends about the $z$ centroidal axis. A strain gage is affixed to the side of the tee stem at a distance of $c=1\mathrm{.}25in.$ below the top surface of the tee shape. After loads are applied to the beam, a normal strain of ${}_x=-810$ is measured by the strain gage. What is the bending stress at point $H?$

FIGURE P$8\mathrm{.}9$