Each arm of a porter governor is 150 mm long and is hinged at a distance of 40 mm from axis of rotation. The mass of each ball is 1.5 kg and of the sleeve 15 kg. When the links are at 30 to vertical, the sleeve begins to rise at 250 rpm. The maximum speed of rotation when the inclination of arms to vertical is 45 (assume friction is constant) (a) 301 rpm (c) 292 rpm (b) 282 rpm (d) 324.5 rpm