单项选择题
A.the chief engineer must be informed at first
B.the captain must be informed at first
C.it must be taken by the duty engineer
D.the generator engine must be stopped
单项选择题 In the engine department, the （） is looked upon to provide the leadership that is needed.
单项选择题 （） is a precaution which contributes to avoiding trouble under normal operating conditions.
单项选择题 Self-excited a-cgenerator with "error operated" voltage control systems draw the full excitation power for the machine terminalsThis dispenses with the current transformers, reactors and capacitors necessary for accurate compounding, but renders the excitation system vulnerable to variations in its output voltageWhich of the following is correct about the generator mentioned according to the sentences above （）.