Why is survival important in the city of ember

Survival in a Dying City
A central conflict in "The City of Ember" is the dying underground city. The city suffers from a food shortage, and it is running low on electricity because the central generator is out of fuel. Lina and Doon discover that government corruption has led to the dire circumstances and hostage-like living conditions. They embark on a dangerous mission to find an exit door out of the crumbling underground city, according to Kirkus Reviews.

Ember is the setting of Jeanne DuPrau's 2003 science fiction novel. The city is an underground refuge in a post-apocalyptic world, and perhaps the most important characteristic is the electricity. All the citizens of Ember have only ever known the lights that define their days instead of the sun—in fact, they don't even know they're living in a city built to survive the apocalypse. To them, it's just home. The city incorporates a river, which powers the generator. One of the main characters, Lina, "knew about the generator, of course. In some mysterious way, it turned the running of the river into power for the city" (67). It has been so long since the inhabitants of Ember first settled in the underground city that all they know is that there is a generator and a river, and somehow the two power their entire lives.
Being in such a contained space for over two hundred years, there's bound to be some conflict. Although it doesn't seem to be a conflicted place, the city still has some physical characteristics of the power structure in the architecture:
The mayor's office was in the Gathering Hall . . . And there were offices for the guards who enforced the laws of Ember, now and then putting pickpockets or people who got in fights into the Prison Room, a small one-story structure with a sloping roof that jutted out from one side of the building. (62)
Here, the reader can see that the Mayor's status is reinforced by his office being in what is presumably the most central location. The guards are an extension of the Mayor's reach; therefore, they also have offices in that central location. The prison being only a room tells the reader two things: firstly, that the control of the mayor is fairly absolute (especially in that the worst infractions are pickpocketing), and secondly, that it's possible the Prison Room was an add-on that the Builders hadn't thought necessary, pointing to the issues surrounding a population trapped in a very small area.
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ADAH RUBENS
CERTIFIED EDUCATOR
The city of Ember is more than 200 years old. It was built when the people realized they needed to find a way to preserve the human race in the event of an apocalyptic catastrophe. They decided to build a city underground and sent only elders and babies to live there. When the babies became adults, they left their caregivers and produced offspring, which is how the city has managed to exist for over two centuries.
The city of Ember has everything a normal city above ground would have: schools, post offices, hospitals, living and work facilities, stores, and even a big town square. It runs on electricity, but it is actually powered by a broken generator that needs to be fixed or replaced. The city also has a lot of pipes, and a river running through them supplies the people with water. On the outskirts of Ember, there is a greenhouse where all the food that is sold fresh and raw is produced. After that, there is an unexplored dark territory—the people are forbidden from going there

Mark Brainliest

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