The equivalent for G3 and G4 is (for series)

1/G34 = 1/G3 + 1/G4

G34 = (2/3) S

Since G1, G2 and G34 are parallel

G1234 = 2/3 + 2/3 + 2/3 = 2 S

I1 = (G1234)(V) = (2 S)(2 V) = 4 amp (also = I5)

I2 = G1V = (2/3 S)(2 V) = 4/3 amp

I3 is the same as I2

I4 = G34 V = (2/3)(2) = 4/3 amp

Check I2 + I3 + + I4 = 4/3 + 4/3 + 4/3 = 4 amp = I1

Answer is E

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