Is my landlord required to provide a working light in the hallways of my apartment building?

When I moved in none of the lights in the hallways of my two-story apartment building worked. At night when I come home from work it is pitch black dark and i have to use a flashlight to get up and into my apartment. I told him about this and the maintenance guy put a bulb in the downstairs hallway but said he'd have to replace the fixture in the upstairs hallway. This way last Friday and it's still not fixed. I called his secretary and she said she was "going to have to see what the landlord wanted to do about it". She also said that they were still looking into what type of fire detectors were required by code before they would put any in my apartment. They still have not put any in after a week and i have none. I thought this was required by law. Last Friday my central air quit working and it's 80 degrees in the apartment. I can't open my windows because there aren't any screens. I also thought the courts looked at the warranty of habitability. What can I do in this situation?