单项选择题
Each hose used for transferring vapors must（）.
A.have a design burst pressure of at least 25 psig B.be capable of withstanding at least 2.0 psi vacuum without collapsing or constricting C.be electrically continuous with a maximum resistance of ten thousand ohms D.All of the above
单项选择题 Each hand portable，semi-portable and fixed fire extinguishing unit on a ship must be tested and inspected at least once every（）.
单项选择题 Each hand portable fire extinguisher on a ship must be marked with（）.
单项选择题 Each fire pump on a tanker must have a pressure gauge located at（）.
