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5. A painting in an art gallery has height h = 4 m and is hung so that its lower edge is a distance d = 3 m above the eye of an observer. If an observer is approaching the wall at a rate of 4 m/s, how fast is the measure of the angle 0 subtended at his eye by the painting changing when the observer is 10 m from the wall? h Teed bluode howamgate