In the book breadwinner chapter 6 why isn’t nooria chosen to be the breadwinner?

Because no one would believe her

Explanation:

Nooria isn't chosen to be the breadwinner because she was the oldest and she said that no one would believe her because  "No one would believe me to be a boy," Nooria said calmly,

looking down at her body. Nooria being calm just made

Parvana madder. ".She also had to watch the little kids.

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.