单项选择题
A.a helix B.a helicoidal C.a curve D.a cone
When a point rotates about an axis and, at the same tim...
单项选择题When a point rotates about an axis and, at the same time, moves parallel to that axis, it describes （）.
A.a line B.a circle C.a helix D.an epllicate
An emergency bilge pumping system is provided and shoul...
单项选择题An emergency bilge pumping system is provided and should be （） of the main bilge pumping system, according to the SOLAS 74 Convention.
A.dependent B.in dependent C.in series D.in parallel
The fire pumps must be capable of delivering a total qu...
单项选择题The fire pumps must be capable of delivering a total quantity of water at a defined head, not less than （） of the total bilge pumping capacity.
A.one-third B.two-thirds C.one-fourth D.two-fourths
