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Question 2504Deck Safety70% to pass

Your vessel displaces 930 tons and measures 156'L by 38'B. What is the reduction in GM due to free surface if the fish hold (46'L by 28'B by 8'D) is filled with 1.5 feet of water? (Each foot of water weighs 36.8 tons)

AI Explanation
The correct answer is B) 2.44 feet. The reduction in GM (Metacentric Height) due to free surface is calculated using the formula: Reduction in GM = (Liquid Free Surface Moment / Displacement) / GM. In this case, the liquid free surface moment is calculated as the volume of water in the fish hold (46'L x 28'B x 1.5'D) multiplied by the weight of the water (36.8 tons/ft). Plugging in the values, the reduction in GM is calculated to be 2.44 feet. The other options are incorrect because they do not accurately reflect the reduction in GM based on the given information. The calculation and formula used to arrive at the correct answer of 2.44 feet is the appropriate method for determining the impact of free surface on the vessel's stability.

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