A governor of Proell type has each arm 250 mm. The upper and lower ends of the arms are pivoted on the axis of the governor sleeve. Each ball has a mass of 15 kg and attached to the extension of the lower arms which are 100 mm long. The minimum and maximum radii of the governor are 125 and 175 mm. The central sleeve is of mass 75 kg. Determine the range of equilibrium speeds, assuming that the extensions of the lower arms are parallel to the governor axis, at the minimum radius.