For lasers with tightly controlled wavelengths， approximately how far apart are the centers of adjacent wavelengths when 100 GHz spacing is used in a DWDM system？ （）

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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?（）

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• After extinguishing a fire with CO2，it is advisable to（）.

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• For lasers with tightly controlled wavelengths, approximately how far apart are the centers of adjacent wavelengths when 100 GHz spacing is used in a DWDM system?（）

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• I hereby（）you，on behalf of the Loocki Grain Co.，Lisbon，to pay to the Harbor Master of the Santa Marta，Columbia，the sum of 500，000 Peso which represents a fine levied on the above-named vessel for polluting the coastal waters with oily water.

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• Love was in the air in a Tokyo park as normally staid Japanese husbands gathered to scream out their feelings for their wives, promising（）and extra tight hugs.

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• 一台使用对称共焦腔的CO2Laser，L=1m，=10.6，基模的腰斑半径为（）：

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• In optical transmission systems， chirped lasers are used for the purpose of：（）.

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• ____ , it is quite easy to drill a hole in it with a laser.

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• If you applying for a particular position your cover letter will need to be tightly focused to explain your suitability for that job.

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• Mickey favored tight skirts with a ___________ at the knee.

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• Despite a very tight schedule, everyone who came to the meeting agreed that a t least one day should be _____ for sightseeing.

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• A. of B. for C. with D. in

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• Weightlifters usually ______ the belt on the waist as tightly as possible before getting onstage for the competition.( )

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• The men who race the cars are generally small,with a tight, nervous look.They range from the early 20s to the middle 40s, and it is usually their nerves that go first.

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• Several industrial processes produce waste gases containing carbon monoxide. Normally these waste gases contam no oxygen. They may be considered as mixtures of CO and N₂. If they contain enough CO, it is common practice to mix them with air and burn them, using the heat released to generate steam or for some other practical purpose.

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• 听力原文：Once you have arrived in our country, beware those professional pickpockets. Here's how to protect yourself. Women whose bags are hanging in front of them are tricky for the thieves, as there isn't a blind side. If you want make it even harder, use a bag with handles rather than a strap. For men, one of the best places to keep a wallet is in the back pocket of tight trousers. You'll feel any attempts to move it. Another good place is in the buttoned-up inside pocket of a jacket. There's just no way in. Even better, keep wallets attached to a cord or chain that is fastened to a belt.

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• Dolphin-assisted therapy for children with mental ...

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• “No, no, go not to Lethe, neither twist Wolf’s-bane, tight-rooted, for its poisonous wine; Nor suffer thy pale forehead to be kiss’d By nightshade, ruby grape of Proserpine;” This excerpt comes fro

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