55. Two copper wires are connected in parallel. Both wires have the same resistivity, p≈2.0 x 10-8 Ω•m. Wire A has length 200 m and cross-sectional area 1.0 mm². Wire B has length 300 m and cross-sectional area 0.5 mm².
What is the equivalent resistance of the two-wire combination?
(A) 2.0 Ω
(B) 3.0Ω
(C) 4.0Ω
(D) 8.0 Ω
(E) 12.0Ω

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統計： A(0), B(3), C(0), D(0), E(0) #3847831