Question 2088 Deck Safety

The correct answer is D) total displacement. To calculate the free surface correction, it is necessary to divide the free-surface moments by the total displacement of the vessel. This is because the free surface effect reduces the vessel's righting arm, which is proportional to the total displacement, not just the lightweight or deadweight. The other options are incorrect because the free surface correction is not directly related to the lightweight, total weight of liquid loads, or deadweight. The free surface effect impacts the overall stability of the vessel, which is best represented by the total displacement.