单项选择题

Routine maintenance of lead acid batteries should include （）.

A.keeping the terminals clean
B.coating cable connections with petroleum jelly
C.maintaining a trickle charge
D.All of the above

<上一题目录下一题>

热门试题

单项选择题

Under which of the listed conditions can the engine room retake the throttle control from the bridge（）.

A.Any time it is deemed necessary
B.Only with the masters permission
C.After a 10 minute delay to the input command
D.Only after the throttle has been placed in stop

单项选择题

Copper is often used as an electrical conductor because it （）.

A.has high resistance at low temperatures
B.has a highly polished surface
C.is able to pass current with little opposition
D.holds insulation together well