Your vessel's has a beam of 40 feet, and you observe a still water rolling period of 20 seconds. What is the vessel's metacentric height?

Correct Answer: Option C — 0.8 ft.

Using the rolling period formula GM = (f * B / T)^2, a 40-foot beam combined with a 20-second rolling period and standard coefficient f = 0.40 results in a metacentric height of 0.8 ft.