A towed caravan, of mass 600 kg is attached by a ball hitch to a car. They are driven round a corner of 35 m radius. The coefficient of friction is 0.5 between caravan wheels and wet road. The centre of gravity of the caravan is 1.2 m above the road. Half the track (distance laterally between wheels) is 0.85 m. Calculate the maximum speed in m/s that the caravan can go round the corner without overturning or sliding.