The three$-$celled tube$-$section shown below is subjected to a twisting moment, $T=100,000in-lb.$ Compute the shear flows, the maximum shear stress, and the rate of twist. Given, the shear modulus, $G=12{10}^6,$ and the thickness, $t_1=0\mathrm{.}1in.,t_2=0\mathrm{.}2in.,$ and $t_3=0\mathrm{.}125in.$