Question 2487 Deck Safety

The correct answer is C) .72 ft. The reduction in GM (Metacentric Height) due to free surface effect can be calculated using the formula: Reduction in GM = (I/V) * (1 - SG_liquid/SG_water), where I is the moment of inertia of the free surface, V is the volume of the vessel, and SG_liquid and SG_water are the specific gravities of the liquid and water, respectively. In this case, with the given tank dimensions and specific gravity of the alcohol (0.8), the calculated reduction in GM is 0.72 ft. The other options are incorrect because they do not accurately reflect the reduction in GM based on the provided information.