A worm is at the bottom of a 10ft hole. He starts climbing out of the hole, climbing 3 feet in one hour. Then he takes a break for 1 hour and slides backward 1 foot. He repeats this pattern, climbing at a constant rate of 3 feet per hour and then sliding backward for an hour until he reaches the top. If the worm begins crawling at 9 am, what time will he reach the top of the hole.