Verified answer

E1=8 B  E2=4 B   r1=0.2 Ом   r2=0.8 Ом  R=5 Ом   U1=?

I=(E1+E2)/(R+r1+r2)=(5+2)/(5+0.2+0.8)=2 A

U1=I*r1=2*0.2=0.4 B

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