PART III $(25$ PTS$)$

A BENDING MOMENT OF $28$ K $-$FT ACTS ON THE CROSS$-$SECTION AT AN ANGLE OF $25$ FROM THE VERTICAL. FIND THE NORMAL STRESS AT A AND $B.$

${}_A=-6\mathrm{.}06\frac{k}{i}{n}^2$

${}_B=5\mathrm{.}10\frac{k}{i}{n}^2$