Dollar coins have never been very popular in the United States since the removal of specie coins from circulation. Despite efforts by the government to promote their use, such as the Presidential $1 Coin Program, most Americans currently use the one-dollar bill rather than dollar coins.
Width and Height. An interior passage door is any door that you use to move from one room to another, and the code requires these to be 80 inches in height. Because this corresponds to 6 feet 8 inches, door manufacturers refer to this as a 6/8 door.
Standard door height. As you can see above, the height of a 'standard' door in Australia is 2040mm. A lot of new homes are being built with taller (e.g. 2700mm) ceilings these days though, and for that reason many people are opting for taller 2340mm tall doors.