单选题The crank throws are displaced from （） to obtained the same number of degrees between the different crank throws.A one anotherB the otherC each otherD each others

A position that is obtained by using two or more intersecting lines of position taken at nearly the same time，is a(n) ______.

A.fix

B.running fix

C.estimated position

D.dead-reckoning position

If the meter needle of the oxygen indicator cannot be set to zero，what should be done ________．

A.Replace the batteries

B.Check the sampling tube for blockage

C.Adjust the final reading by the amount the needle is displaced from zero

D.Replace the platinum filament

A.Me

B.I

C.Mine

D.my

The number and position of hydrants arranged on board shall be such that _______，one of which shall be from a single length of hose，may reach any part of the ship normally accessible to the passengers or crew while the ship is being navigated．

A.at least two jets of water which shall be from the same length of hose

B.at least two jets of water emanating from the same hydrant

C.at least two jets of water not emanating from the same hydrant

D.at least two jets of water not emanating from the same hydrant，one of which shall be from a single length of hose

To predict the actual depth of water using the Tide Tables，the number obtained from the Tide Tables is ______．

A.the actual depth

B.added to or subtracted from the charted depth

C.multiplied by the charted depth

D.divided by the charted depth

Your radar is set on a true motion display．Which of the following will NOT appear to move across the PPI scope ________．

A.Echoes from a buoy

B.Own ship's marker

C.Echo from a ship on the same course at the same speed

D.Echo from a ship on a reciprocal course at the same speed

On a medium-speed main propulsion diesel engine, the crank-pin or crank journalbearings receive lubricating oil from( ).

A.a spindle lubricator

B.an oil jet

C.internal splashing

D.drilled passages in the crankshaft