The electric wires in a house____with some kind of insulation.

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• Your vessel is equipped with a fixed CO2 system and a fire main system. In the event of an electrical fire in the engine room what is the correct procedure for fighting the fire?（）

  A . Use the CO system and evacuate the engine room B . Use the fire main system and evacuate the engine room C . Evacuate the engine room and use the CO system D . Evacuate the engine room and use the fire main system

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• A circuit that has one wire in contact with the hull of the ship is a（）

  A . series circuit B . grounded circuit C . short circuit D . closed circuit

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• The resistance of electric wire will decrease as its （）

  A . length increases B . cross-sectional area increases C . temperature increases D . percent of metallic purities increase

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• If a CO2 fire extinguisher is not readily available, which of the listed fire extinguishers would be best suited to combat a small electrical fire in a switchboard?（）

  A . Dry chemical B . Halon C . Low velocity fog D . Steam

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• A new（）will be set up in this area so we will have enough electricity in the future.

  A . power station B . electricity station C . power factory D . electrical statio

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• The coil of wire rotating in the magnetic field produces the（）.

  A . voltage B . current C . power D . frequency

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• On your vessel，a wire rope for the cargo gear shows signs of excessive wear and must be replaced. In ordering a new wire for this 10-ton boom，what safety factor should you use?（）

  A . Three B . Five C . Six D . Seve

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• In modern fathometers the sonic or ultrasonic sound waves are produced electrically by means of a(n)（）.

  A . transmitter B . transducer C . transceiver D . amplifier

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• Your vessel is equipped with a fixed C02 system and a fire main system. In the event of an electrical fire in the engine room what is the correct procedure for fighting the fire?（）.

  A . Use the C0 system and evacuate the engine room B . Use the fire main system and evacuate the engine room C . Evacuate the engine room and use the C0 system D . Evacuate the engine room and use the fire main system

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• Which of the following electric motors would be the safest and most reliable to use on the main deck of a vessel in foul weather conditions?（）

  A . Sealed motors B . Drip proof motors C . Enclosed motors D . Watertight motor

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• The （） compressor and its electrical motor are entirely housed in a gas-tight casing.

  A . open-type B . hermetic C . A and B D . None of the above

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• The correct way to make an eye in a wire rope with clips is to place the clips with the（）.

  A . first and third U-bolts on the bitter end and the second U-bolt on the standing part B . first and third U-bolts on the standing part and the second U-bolt on the bitter end C . U-bolts of all clips on the bitter end D . U-bolts of all clips on the standing part

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• You have a large，broken-down vessel in tow with a wire rope and anchor cable towline. Both vessels have made provision for slipping the tow in an emergency; however，unless there are special circumstances（）.

  A . the towing vessel should slip first B . the vessel towed should slip first C . they should slip simultaneously D . either vessel may slip first

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• The only wire rope termination which may be made in the field is（）.

  A . swaged socket B . thimbled mechanical splice C . hand splice D . spelter poured and resin socket

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• A ground in an electrical circuit outside the engine room （）.

  A . cannot be detected tinder normal conditions B . is of no consequence to engineering personnel C . is indicated at the branch circuit breaker panel D . is indicated by the ground detecting lamps on the main switchboard

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• When there is a fire in a large electric motor, normally the very FIRST step is to （）

  A . secure the electric supply B . ventilate area to remove smoke C . start the fire pump and lead out hose D . apply foam

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• The main purpose of an electric space heater installed in a large AC generator is to （）

  A . prevent the windings from becoming brittle B . prevent moisture from condensing in the windings during shutdown C . prevent acidic pitting of the slip rings D . keep the lube oil warm for quick starting

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• In working out a local apparent noon sight for your latitude，you subtract the Ho from 90°. The 90°represents the angular distance from（）.

  A . the equator to the elevated pole B . your horizon to your zenith C . your zenith to the elevated pole D . the geographical position of the Sun to the elevated pole

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• The electric fan has blown away the terrible smell in the hall,（）?

  A . can't it B . isn't it C . hasn't it D . doesn't it

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• When a rescuer finds an electrical burn victim in the vicinity of live electrical equipment or wiring，his first step is to（）.

  A . flush water over any burned area of the patient B . apply ointment to the burned areas on the patient C . get assistance to shut down electrical power in the area D . remove the patient from the vicinity of the live electrical equipment or wiring

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• Given the same water depth and line tension，the holding power of a 19 pound/foot wire rope mooring system in comparison to the holding power of a 90 pound/foot chain mooring system will be（）.

  A . weaker B . equal C . greater D . indeterminable

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• In automatic （） the winch may be overhauled and wire is paid off the barrel at a pre-determined maximum tension.

  A、cranes B、windlass C、capstans D、mooring winches

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• ____ are chemical messengers in the transmission of impulses that trigger the receptors on the next nerve cell’s dendrites to produce a new electrical current.

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• 听力原文： Frozen forever in time are memories of wire rimmed glasses and a grey sweater that almost always had chocolate covered raisins in the left pocket. Grandpapa always read to me. I’d sit beside him and listen.

  When Grandpapa got old & couldn’t see well enough to read anymore, I read to him. I’d read until his eyes closed and he started to fall asleep. As I quietly got up, Grandpapa would reach into the pocket of his grey sweater and pull out a box of chocolate covered raisins, pressing them into my teen-aged hand. Eyes still closed, he would whisper "I remembered". Grandpapa always said things like; "You scratch my back an’ I’ll scratch yours," and "Share, little one. Sharing makes everything better. ’ Somehow, everything always was better. I’ll never forget the call from the hospital. Grandpapa had suffered a heart attack. My Mother was so upset, crying so many tears. It was snowing that night. Great big fluffy snowflakes falling through the glow of the streetlight. It’s snowing this morning, big fluffy snowflakes fall through the glow of the streetlight. I sit and watch the snowflakes fall, thinking about Grandpapa with love in my heart and a cup of coffee in my hands. I will always remember his wise words, "Sharing makes every thing better. ’ The need to reach out to another human being is instinctive, and as necessary as the air that we breathe. It is my sincere hope that you will want to share something of yourself. A kind word to a stranger perhaps, or a compliment to someone that deserves one. It is these small act a of sharing, and caring, that make this world a better place. (33) A．chocolate covered raisins. B．chocolate covered peanuts. C．a banana. D．an apple.

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