Why does my 1997 nissan altima make a squealing no

[jimmy2112]

I own a 1997 nissan altima with over 100k miles. A loud squealing noise comes from the front wheels. It is especially loud at slow speeds and barely noticable at higher speeds. I don't think it's the rotors because it makes the noise when I'm not applying the breaks at all.
The car is parked for extended periods of time (two to four months) while I am away at school.
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used nissan altima
used toyota corolla