While underway，in fog，you hear a whistle signal of one prolonged blast followed by two short blasts. This signal is sounded by a vessel（）.

A . enter the tank safely B . suspect the accuracy of the reading C . ventilate the tank D . test for nitroge

A . middle of the channel B . starboard side of the channel C . port side of the channel D . side of the channel that has the widest tur

A . the bearing had been overheated B . water was present in the oil C . the lube oil was not being properly filtered D . the maximum allowable bearing pressure had been exceeded

A . station the look-out in the wheelhouse to keep a continuous watch on the radar B . secure the sounding of fog signals until a vessel closes within five miles C . station a look-out as low down and far forward as possible D . keep the radar on the shortest available range for early detection of approaching vessel

A . you must visually signal oncoming vessels B . you must immediately tie up in the nearest port until the radiotelephone is repaired C . you must anchor until the radiotelephone is repaired D . the loss of the radiotelephone must be considered in navigating the vessel

A . come right B . sound the danger signal C . continue on your course D . come left

A . stop your engines B . sound two prolonged blasts of the whistle C . sound the danger signal D . slow to bare steerageway

A . stay near the middle of the channel B . keep to the starboard side of any vessels you meet C . exchange whistle signals with any other vessels in the channel D . keep to the side of the channel which lies to your starboard

A . Your speed must be reduced to bare steerage ways B . A look-out is not required if the radar is on C . The radar should always be kept on a short-range scale D . Fog signals are only required when a vessel is detected by radar

A . Middle of the channel B . Starboard side of the channel C . Port side of the channel D . Side of the channel that has the widest tur

A . Secure the applicators to preserve the charge in the cylinders B . Continue with your work as there is nothing you can do to stop the flow of CO C . Retreat to fresh air and ventilate the compartment before returning D . Make sure all doors and vents are secured

A . one blast，4 to 6 seconds in duration B . three blasts，4 to 6 seconds in duration C . one continuous blast until you are able to see around the bend D . one blast，8 to 10 seconds in duratio

A . During an engine speed change B . During a navigational course change C . Unless the helm is in the“hand”mode D . All of the above

A . Figure eight turn B . Round turn C . Racetrack turn D . Williamson tur

A . vessel not under command B . sailing vessel C . vessel being towed (manned) D . vessel being towed (unmanned)

A . You cannot create a table form within Forms.  B . You must use the FORMS_DDL built-in to create the table.  C . You must use the DBMS_DYNAMIC_DDL package to create the table.  D . You can write the CREATE TABLE statement directly into the trigger.

A . White buoy with a green top B . White and international orange buoy C . Yellow buoy D . Yellow and black vertically-striped buoy

A . Manually trip the over-speed device B . Interrupt the fuel flow to the engine C . Disengage the safety interlock D . Slide the camshaft to the neutral positio

A . stop your engines B . sound the danger signal at two-minute intervals C . hold course and speed until the other vessel is sighted D . take avoiding action as soon as possible

A．what B． which C． those D． that