.​ A deep–sea diver attached to a safety cable was lowered into the water to a depth of 600 feet. During the next hour, the safety cable was let out 250 feet, pulled in 36 feet, pulled in 69 feet, let out 23 feet, pulled in 51 feet, let out 68 feet, and pulled in 24 feet to allow the diver to explore. At the end of the hour, what was the depth of the diver?