A ladder 26 ft long leans against a vertical wall. If the lower end is being moved away from the wall at the rate of 5 ft/sec, how fast is the height of the top changing (this will be a negative rate) when the lower end is 10 feet from the wall? 26 At 26 At The height of the top is changing at a rate of when the lower end is 10 feet from the wall. (Simplify your answer.)