单项选择题 The International Sewage Pollution Prevention Certificate shall be issued for a period specified by the Administration, which shall not exceed from the date of issue（）

单项选择题 When the ship is in restricted visibility, the officer in charge of the engineering watch shall ensure that （） Ⅰ.Bridge order relating to changes in speed or direction of operation areimmediately implemented Ⅱ.auxiliary machinery used for maneuvering is readily available Ⅲ.permanent air or steam pressure is available for sound signals

单项选择题 The officer in charge of the engineering watch shall notify the chief engineer without delay （）.