Aural clues

I'm in my office. I close my eyes and i can know:

how much it's snowed by the almost mute quality of the sounds made by cars in the street outside; that Kwame hasn't peed in a long time because the splashing in the toilet goes on forever; that the air i'm breathing has come to me through tubes, by the whispering of the ventilation system; that my chewing of the gum in my mouth pushes aside the saliva that covers it over and over, by the squelching sounds produced every time i sink my teeth in it; that there is some kind of spring underneath the keys on the computer's keyboard, because i hear them twang faintly when i release them.