Ответ:
k=17.6%
Объяснение:
P1=U²/R1
R1=po*L1/S
P2=U²/R2
R2=po*L2/S
L2=0.85*L1
P2/P1=R1/R2=1/0.85=1.176
k=(1.176-1)*100%=17.6%
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