R1=2 R2=1 R3=2 R4=1 R5=4 R6=2 I1=1 A
U1=I1*R1=1*2=2 B
U6=I1*R6=1*2=2 B
R234=R2+R3+R4=1+2+1=4
R2345=R5*R234/(R5+R234)=4*4/(4+4)=2
U5=U2345=I1*R2345=1*2=2 B
I234=U2345/R234=2/4=0.5 A
I5=I1-I234=1-0.5=0.5 A
U2=I234*R2=0.5*1=0.5 B
U3=I234*R3=0.5*2=1 B
U4=I234*R4=0.5*1=0.5 B
U=U1+U2345+U6=2+2+2=6 B
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