As head of state of the U.S. Government meaning the president is the highest ranking member of government he or she represents the United States as the chief diplomat in interactions with other countries. Also given his constitutional powers he or she is also the commander in chief meaning they are in charge of the military with fits with their overall position as head of the executive branch of the U.S. Government.
I believe the answer is: Formal region
Each formal region would be differentiated by their own unique government structure that separate each region with the other. Each border on the sides of each region would consist of some sort of boundaries ( could be natural or human made) that accepted by all regions as a legal separation between their jurisdiction.
The type of channel that speaker one and speaker two use in their communication would be auditory - b.
The fact that we're talking about "speaker" 1 and "speaker" 2 implies already the fact that both of them are talking and this then implies that they are using the auditory channel of communication.
Can't answer without the text.
