(a) Explain the purpose of load lines. (6)

(b) An oil tanker of 17000 tonne displacement has its centre of gravity 1m aft of midships and has 250 tonnes of oil fuel in its forward deep tank 75 m from midships.

This fuel is transferred to the after oil fuel bunker whose centre is 50m from midships.

200 tonnes of fuel from the after bunker is now burned.

Calculate the new position of the centre of gravity: (10)

(i) after the oil has been transferred,

(i) after the oil has been used.