What are these exactly and how are they powered in my Chevy Cobalt 2005?

[mustafaali93]

what are these and in my radio mp3, there is a compartment for a cassette, can i turn it into an AUX for my ipod

http://i919.photobucket.com/albums/ad34/brownpride7866/Car/0324101845-00.jpg
http://i919.photobucket.com/albums/ad34/brownpride7866/Car/0103102133-00.jpg
http://i919.photobucket.com/albums/ad34/brownpride7866/Car/0324101830-00.jpg