What was Rome's constitution? A. A written collection of laws
B. A set of rulings issued by the Roman kings
C. A process for rising from lower to higher offices
D. A system of to organize government

The Roman Constitution was a historical, unwritten set of guidelines and precedents that changed with Rome's needs. It served as model of administrative checks and balances and ensured the separation of powers

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.