i have a bunch of photos in the photos app that comes with the ipad. i can delete the photos thats on my camera roll but i uploaded some photos from my computer directly to my ipad 2 using usb thing. i want to delete one of those photos but i cant find a way to do that. the little trashcan symbol doesnt show up on those photos like it does on the camera roll photos. how can i delete the photos i uploaded/synced from my computer using the usb thing?