单项选择题
Which operation should be done when launching an inflatable liferaft by hand?（）
A.Open the liferaft casing B.Turn the valve on the CO2 cylinder to start inflation C.Make sure the operating cord is secured to the vessel before throwing it over the side D.After inflation，detach operating cord from liferaft
单项选择题 Which of following data is NOT painted on the bow of a lifeboat?（）.
单项选择题 When whistle signals are used for launching lifeboats，one short blast means（）.
单项选择题 When should you use distress flares and rockets?（）
