单项选择题
Which of the following machinery space operations is required to be logged in the Oil Record Book?（）
A.Ballasting or cleaning of fuel oil tanks
B.Shifting suction of main fuel pump to reserve fuel oil tank
C.Changing out sprayer plates to adjust for steam demand
D.Daily inspection of engine room bilges
单项选择题 The distance between the bottom of the hull and the waterline is called （）.
单项选择题 The lowest temperature at which the vapor formed from a liquid ignites and continues to burn steadily in the presence of an ignition source is called the（）.
单项选择题 Which of the following statements describes one of the functions of the ballast system?（）