单项选择题
You are entering an east coast port and see a buoy with a yellow triangle painted on it.This indicates（）.
A.you are in the vicinity of the ICW B.the buoy is a special mark C.the buoy is off station D.the buoy designates a sharp turn in the channel
单项选择题 You are drifting in a locale where there is no current．As a rule，your vessel will lie（）.
单项选择题 You are approaching a vertical lift bridge.You know the span is fully open when（）.
单项选择题 Which vessel would display a cone，apex downward（）.
