a= (V-V(0))/t=(72-54)/5=3.6
R234=12, R2345=12*8/20=4.8, Rэ=6.8, Iэ=U/Rэ=U/6.8=I1=I6, Uбв=U-U*2/6.8=0.706*U, I5=0.706U/8= 0.088U, I2,3,4=0.706U/12=0.059U
Vo=200 л t1=10 t2=60 t3=40 V2=?
m=po*V
V1*(t3-t1)=V2*(t2-t3)
V2=V1*(t3-t1)/(t2-t3)=V1*(40-10)/(60-40)=1.5*V1
Vo=V2+V1=1.5*V1+V1=2.5*V1
V1=Vo/2.5=200/2.5=80 л
V2=1.5*80=120 л
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U=I*R=4,4*50=220 B
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