34/9 ??
Release i1 from 4V bater in anticlockwise,i2 from 6V battery in clockwise
4-8(i1+i2)-6i1-2i1=0
=> 4=16i1+8i2 ----------(1)
and 6-4i2-8(i1+i2)-1i2=0
=> 6=8i1+13i2 -----------(2)
SOlving we get i2=8/18
i1=1/36
VA=AD
VD-8(i1+i2)=VC
VD-VC=8(i1+i2)
VD-VC=34/9
there may be some caculation mistakes..but method will be same [1]