In quadrantal bearing system, back bearing of a line may be obtained from its forward bearing, by
(A) Adding 180°, if the given bearing is less than 180°
(B) Subtracting 180°, if the given bearing, is more than 180°
(C) Changing the cardinal points, i.e. substituting N for S and E for W and vice-versa
(D) None of these
(A) Adding 180°, if the given bearing is less than 180°
(B) Subtracting 180°, if the given bearing, is more than 180°
(C) Changing the cardinal points, i.e. substituting N for S and E for W and vice-versa
(D) None of these