单项选择题
ECDIS should be capable of（）all chart information necessary for safe and efficient navigation originated.
A.Exhibiting B.Existing C.Demonstrating D.Displaying
单项选择题 （）is main emergency fire system in all merchant ships.
单项选择题 Each fire drill shall not include（）.
单项选择题 Which instrument is used to measure the relative humidity of air?（）
