1) 1/Ro=1/R1+1/R2+1/R3=1/3+1/2+1/6=1
Ro=1 Ом
U1=U2=U3=Uo=24 B
I1=U1/R1=24/3=8 A
I2=U2/R2=12 A
I3=U3/R3=24/6=4 A
Io=I1+I2+I3=8+12+4=24 A
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2) Io=I1=I2=I3=U1/R1=16/29=0.6 A
R2=U2/I2=12/0.6=20 Ом
U3=Uo-(U1+U2)=77-(16+12)=49 B
R3=U3/I3=49/0.6=81.7 Ом
Ro=R1+R2+R3=29+20+81.7=130.7 Ом
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