What runs along the eastern side of central africa

Explanation:

google: Tondou Massif, French Massif du Tondou, plateau region in the eastern Central African Republic, near the border with South Sudan. ... The watershed between the Congo and Nile river systems, defining most of the boundary between the Central African Republic and South Sudan, passes along the eastern edge of the plateau.

me:

The Central African Republic is, in essence, an undulating plateau. Central and south are a series of forested, rolling hills, with some topping 2000 ft. A dense tropical rainforest in the southeast fronts the Ubangi River, and in the north, the land flattens into a treeless, desert-like savanna grassland.

most cajuns resided in acadiana, where their descendants are still predominant

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.