1 - г
U=(R1+R2)*I=(15+30)*0.4= 24
2- б
R=R1*R2/(R1+R2)=6*12/(6+12)= 4 Ом
3 - б
U=i*(R1+R2)=0.5*(2+2)=2 B
4 - в
I=U/(R/3)=3/(10/3)=0.9 A
5 - г
Rob=R1+R2/2=12+ 12/2=18 Ом
I3=U/Rob=36/18= 2 А
6 - а
Rob=R+ R*2R/(3R)=120+120*240/360= 200 Ом
I1=U/Rob=18/200=0.09 A
U1=I1*R1=0.09*120=10.8 B
U2=U-U1=18-10.8=7.2 B
I2=U2/R2=7.2/120=0.06 A