R45=R4+R5=6+4=10
R456=R45*R6/(R45+R6)=10*15/(10+15)=6
R3456=R456+R3=6+4=10
R23456=R3456*R2/(R3456+R2)=10*10/(10+10)=5
Ro=R23456+R1=5+5=10
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Io=I1=U/Ro=40/10=4 A
U1=I1*R1=4*5=20 B
U2=U23456=I1*R23456=4*5=20 B
I2=U2/R2=20/10=2 A
I3=I1-I2=4-2=2 A
U6=I3*R456=2*6=12 B
I6=U6/R6=12/15=0.8 A
I4=I5=I3-I6=2-0.8=1.2 A
U3=I3*R3=2*4=8 B
U4=I4*R4=1.2*6=7.2 B
U5=I5*R5=1.2*4=4.8 B
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