In Delta to Star (Delta-Wye) conversion, the equivalent star resistance connected to a node is:
AProduct of two adjacent delta resistances divided by sum of three delta resistances
BProduct of three delta resistances divided by adjacent resistance
CDifference of adjacent delta resistances
DSum of three delta resistances divided by three
Explanation
R_star = (R1 * R2) / (R1 + R2 + R3), where R1 and R2 are adjacent delta branch resistances.

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