An ocean linear, 240 m long and 24 m wide, displaces 654 MN of sea-water. The second moment of inertia of the water plane about its fore-aft axis is 2/3 of that of the circumscribing rectangle. The position of the centre of buoyancy is 2.30 m below the centre of gravity. How high is the metacentre above the centre of buoyancy (to the nearest cm)