Verified answer

Ответ:

Объяснение:

1) R12=R1+R2=100+400=500 Ом

R34=R3+R4=100+400=500 Ом

R=R12*R34/(R12+R34)=500/2=250 Ом

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2) R13=R1*R3/(R1+R3)=100*400/(100+400)=80 Ом

R24=R2*R4/(R2+R4)=100*400/(100+400)=80 Ом

R=R13+R24=80+80=160 Ом

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