(a) Explain clearly the meaning of the term 'reserve buoyancy' (6)

(b) A vessel of 10000 tonne displacement has a second moment of area of waterplane about the centreline of 60 x 10^3 m4. The center of buoyancy is 2.75 m above the keel. The following are the disposition of the masses on board the ship (10)

4000 tonne 6.30m above the keel

2000 tonne 7.50m above the keel

4000 tonne 9.15m above the keel

calculate the metacentric height (GM)