（）ofthefollowingneednotbeenteredintheofficiallogbook?
A. Thetestingoftheinternalcombustionenginedrivenemergencygeneratoratleastonceeachmonththevesselisnavigated
B. Thetestingofstoragebetteriesforemergencylightingandsystemsonceeach6monthsthevesselsisnavigated
C. Theactualdraftwhenthevesselarrivesinsaltwaterafterdepartmentaport
D. Thetestingoftheline-throwingapplianceonceevery3months
（）itraintomorrowmorning,theloading（）.
A. Should/willbepostponed
B. If/shallbepostponed
C. Should/wouldbepostponed
D. If/hastobepostponed
正序电压故障点处最低，沿线向电源方向（）。
A. 降低
B. 升高
C. 先降低后升高
D. 先升高后降低
我国制定的标准额定电压分为（）类。
A. 1
B. 2
C. 3
D. 4
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