Only way to make sure. Alternatively, throw a pinch of sand on the keyboard, close the lid, bag the Mac. Now, with some vigor, take it out blindly by any corne

Only way to make sure. Alternatively, throw a pinch of sand on the keyboard, close the lid, bag the Mac. Now, with some vigor, take it out blindly by any corner and trow it down on the thick wooden table, slamming it with it's own weight. A few times. And tell me how that gentle test went for you. :)