On a vessel of 9,000 tons displacement, compute the reduction in metacentric height due to free surface in a hold having free water on the tank tops. The hold is 20 feet long and 30 feet wide. What is the reduction in metacentric height?

Correct Answer: Option C — .14 feet

Free surface correction is calculated using FSC = (l * b^3) / (12 * Displacement). For a 20-foot by 30-foot tank on a 9,000-ton vessel, the reduction in metacentric height evaluates to 0.14 feet, accounting for the virtual rise of the center of gravity.