单选题To prevent the overflow of cargo tanks due to expansion, you should top off （）.A to the bottom of the expansion trunkB to within 1% to 3% of its capacityC to within 1% to 3% inches of its capacityD 1 to 3 inches from top of the vent pipe

To determine which grades of cargo a tank vessel is permitted to carry you should ______.

A.refer to the vessel's Certificate of Inspection

B.examine the cargo tanks and fittings

C.ask the terminal supervisor or his representative

D.check the loading order

Why is gas-freeing rarely required for LPG cargo tanks?

A.LPG is compatible with all cargos

B.LPG's high oxygen content makes it nonvolatile

C.Cargo tanks are inspected less frequently than on oil tankers

D.The cargo tanks are used for one type of cargo only

How does an inert gas system on a tanker function to prevent explosions in cargo tanks?

A.De-energizes the "charged mist" effect

B.Maintains a positive pressure on the vent header to cool the flammable vapors

C.Inert gas filters out the flammable vapors from the cargo tank spaces

D.Inert gas dilutes the flammable vapor and air concentrations to keep them below the lower explosive limit

What should you be concerned with when loading and securing vehicles aboard a Ro-Ro vessel ________．

A.That all fuel is drained from the vehicles' tanks to prevent fire hazard

B.The size，weight，and center of gravity of vehicle/cargo unit

C.The preferred stowage of vehicles is athwartships wherever possible

D.The vehicles' brakes should not be set to allow for adjusting the lashings

You are to load styrene in bulk，which is subject to self-polymerization．You must ______．

A.Not carry any cargo in the tanks surrounding the tank loaded with styrene

B.Inject nitrogen to pad any ullage above the styrene to prevent contact with oxygen

C.Be furnished with a Certificate of Inhibition to be maintained on the bridge

D.Use heating coils to maintain the styrene within the temperatures specified by the shipper

In no case shall ballast water be carried in cargo tanks，______ on those rare voyages when weather conditions are so severe that，in the opinion of the master，it is necessary to carry additional ballast water in cargo tanks for the safety of the ship.

A.besides

B.in particular

C.incase of

D.except

You are cleaning the tanks after carrying a cargo of crude oil. Which statement is TRUE?

A.Washing water should be recirculated if possible because it has the same electric potential as the cargo tank being cleaned

B.The hoses to portable cleaning machines should be disconnected before the machines are removed from the tank

C.The principal hazard with steaming cargo tanks is raising the ambient temperature above the flame point of the cargo residue

D.Steam cleaning and water washing are both capable of generating electrostatic charges within a tank

A claim for cargo damages may be held against the shipowner if such damage is the result of failure of the ship's officers to ______.

A.ensure the fitness and safety of cargo spaces

B.ensure adequate packaging of the cargo

C.prevent delays due to quarantine restrictions

D.correct all defects in the ship's construction

Generally speaking，the heavier cargo will go into the ______，distributing it evenly fore and aft，the lighter cargo will probably be placed in the ______．

A.Deep tanks/lower holds

B.Lower holds/tweendecks

C.Tweendecks/deep tanks

D.Deep tanks/tweendecks

Valves on steam-smothering lines to cargo tanks shall be set with ______．

A.The master control valve shut and valves to individual cargo tanks shut

B.The master control valve open and valves to individual cargo tanks shut

C.The master control valve shut and valves to individual cargo tanks open

D.All valves open