how do i slow down the music

Currently, you can't change the tempo of the music through iTunes. If you have a Mac, you can use GarageBand to slow it down.

• Create an empty GarageBand project.
• Drag an iTunes song from the Media Browser to the Track area of GarageBand.
• Show the Editor in GarageBand.
• Enable "Follow Tempo and Pitch" for the track with your song.
• Then change the tempo in the LED display. Your song will no play with a differnet tempo.