Apply Ohm's law in the series branch with R1 and R2 Steps:

• R1 = 0.48 V / 0.32 A = 1.5 Ω.
• The R1-R2 branch shares the full 1.6 V EMF, with current 0.32 A (total cell current 0.6 A splits, 0.28 A through R3 branch).
• Voltage across R2 = 1.6 V - 0.48 V = 1.12 V.
• R2 = 1.12 V / 0.32 A = 3.5 Ω.

Why C is correct:

• 3.5 Ω satisfies Ohm's law (V = IR) for the voltage drop across R2 in series with R1 under the full circuit EMF.

Why the others are wrong:

• A. 5.1 Ω overestimates R2, yielding branch resistance mismatch with total 2.67 Ω.
• B. 2.5 Ω underestimates R2, inconsistent with 1.12 V drop at 0.32 A.
• D. 5.0 Ω approximates A but fails exact total resistance calculation.

Final answer: C