Six resistors are connected so as to form the edges of a tetrahedron ABCD, the resistances of opposite pairs being equal. (Note that the resistors AB and CD do not touch each other) find the equivalent resistance between A and C.
A. `(r_(3))/(2)[(2r_(1)r_(2)+r_(3)(r_(1)+r_(2)))/((r_(1)+r_(3))(r_(2)+r_(3)))]`
B. `(r_(2))/(2)[(2r_(1)r_(2)+r_(3)(r_(1)+r_(2)))/((r_(1)+r_(3))(r_(2)+r_(3)))]`
C. `(r_(1))/(2)[(2r_(1)r_(2)+r_(3)(r_(1)+r_(2)))/((r_(1)+r_(3))(r_(2)+r_(3)))]`
D. `(r_(3))/(2)[(2r_(1)r_(3)+r_(2)(r_(1)+r_(2)))/((r_(1)+r_(3))(r_(2)+r_(3)))]`
