$(40\%)$ The simply suppotted beath shown in Figgte $1($a$)$ has the cross section shown in I $($b$).$

$($a$)$ Find the maximum bending stress and evaluate the percentage of bencling moment resisterl by

the flange ateas in a cross section.

$($b$)$ Find the maximum sheat stress and evaluate the percentage of shear force resisted by the

web in a cross section.

$($c$)$ Show that the shear flow in the web becomes constant if the web area does not resist

normal stress at all.