单项选择题
A.one salt water, one fresh water B.one salt water, one fuel C.one fresh water, one fuel D.one steam, one fuel
Auxiliary machinery covers everything onboard except （）...
单项选择题Auxiliary machinery covers everything onboard except （）.
A.main engines B.main boilers C.pipes and fittings D.A and B
A （）, sometimes called filters, is a device designed to...
单项选择题A （）, sometimes called filters, is a device designed to prevent the passage of unwanted solids into the system.
A.steam trap B.check valve C.separator D.strainer
To maintain the down stream pressure within defined lim...
单项选择题To maintain the down stream pressure within defined limits over a range of flow and despite any changes in supply pressure, （） is fitted.
A.a check valve B.a gate valve C.a pressure reducing valve D.a quick closing valve
