One characteristic of dictatorships is that select one: a. they lack judicial and legislative powers. b. rulers cannot be held responsible to the will of the people. c. they are always ruled by a single individual. d. their power over the people is limited

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.