New member just joined. sorry im pretty sure there are already post about this but i can't seem to find any. Recently i discovered two cracks, about maybe a little less than 3 inches in length. These cracks are near the bottom corners. I have never dropped my macbook and i take good care of it for the most part. What could be the cause of this and where&how much would it cost to repair. If anyone can let me know it would be much appreciated. THANKS!