Frame $\frac{?}{{?}_{\frac{?}{?}}BCD},$ as shown below, is on a horizontis phane and is loaded with a verfical distributed

load q$.$ A$.$ B$.$ Cand D are fixed for both texure and torsion. E and F are rigid eonneetions for both

flexure and torsion. The section lor all the membersis shown below, $L_L=400cm,L_2=800cm,$

and $q=1$ tf$/$m Take into account tho torsional effect; unelading St Venant torsioti and warping

torsion. of Members AB & CD$.$ and deternine $(1)$ moment distribution of Member EF: $(2)$ torsion

distribution of Member AB; and $(3)$ stress distribution of the section at A$.$ Use $E=2000t\frac{f}{c}{m}^2$

and $G=780t\frac{F}{u}{m}^2$