单项选择题 Personnel boarding a davit-launched liferaft from a ship should be checked to assure they are not in possession of or wearing（）.

单项选择题 On inflatable liferafts，the operating cord should be renewed by（）.

单项选择题 Inflatable liferafts shall be serviced at an approved servicing facility every 12 months or not later than the next vessel inspection for certification. However，the total elapsed time between servicing cannot exceed（）.