1)R2R3并联电阻为4K，加R1的2K，总电阻为6K，所以u2=100x4/6=66.67Vi2=i3=66.67/8=8.33m A，2)U2=100x 8/(2+8)=80V， i2=100/(2+8)=10m A i3=03)u2=0 i2=0 i3=100/2=50m A
