Explanation: The difference (degree) in the magnitude of the fore bearing and back bearing of any line is 180° or if the difference is exactly 180°, the two stations may be considered as not affected by local attraction. For regular hexagon, Sum of interior angles = (n - 2)180°
Sum of interior angles = (6 - 2)180° = 720° Each interior angle =
720
6
=120° Back bearing = 180° + Fore bearing = 180° + 36°45' = 216°45' ∴ Fore bearing of BC = 216°45' - 120° = 96°45'