For a fully transposed transmission line,

positive, negative and zero sequence impedances are equal
positive and negative sequence impedances are equal
zero and positive sequence impedances are equal
negative and zero sequence impedances are equal

Correct answer: positive and negative sequence impedances are equal

Solution

In a fully transposed transmission line, the phase impedances are averaged over the line length, making the positive- and negative-sequence impedances equal. The zero-sequence impedance is generally different because the return path is not the same. Hence, positive and negative sequence impedances are equal.

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