2.78 meters (this is a disaster and a dead end) is the number of big killers. (Yang Zhai ruler) No matter the height or width of the door, it is a big killer.
(Ding Lan's ruler is in the righteous bureau, your son is in the good bureau, and the yin house uses his ruler. )
Lu ban feng shui ruler, one foot points yin and yang. Guys, don't use yin and yang wrong.