I just bought a macbook air 13 inch, and have a question: If I'm using my macbook air and just let it sit open then it turns black (gone to sleep?). when I hit any key the screen comes back almost instantly. If I'm using my macbook air and close it, then open it later again, it takes 3~4 seconds to come back to life, which seems about as long as it takes for the computer to boot up after I completely shut it down. Is the computer shutting down instead of going to sleep when I close the lid? Is there a way I can get it to just go to sleep like when it sits idle, so that when I open the lid it just comes back to life immediately instead of 3~4 seconds? I realize this might be a really dumb question but any help would be greatly appreciated. Thanks!