Unlike the other courts of appeals, the court of appeals for the federal circuit hears appeals from territorial courts hears cases from a federal regulatory agency hears appeals from the u. s. tax court hears cases from all over the united states

the 4th option is the answer

an informal structure in a bureaucracy would be something like so-called "office politics". where there's a formal structure set up for the organization, but then an informal subculture as well that has a way of organizing the bureaucracy further. this can be positive because it sets up an added degree of organization, albeit informal, within the bureaucracy.