A.ε=2g(Q-P)/RW B.ε=2g(Q+P)/RW C.ε=2g(Q+P)/R(W+2Q+2P) D.ε=2g(Q-P)/R(W+2Q+2P)

A.ε=2g(Q-P)/RW B.ε=2g(Q+P)/RW C.ε=2g(Q+P)/R(W+2Q+2P) D.ε=2g(Q-P)/R(W+2Q+2P)

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