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当流体在管内流动时，若Re<2300时，流动为层流。Re>10000时，流动为紊流。
A . 正确
B . 错误
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流体在管内流动时，当雷诺数Re≤2000时为（）流动，当Re≥2300时，流体流动为（）。
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液体在光滑金属圆管流动Re＝1500、Re＝2500时，各为何流态？
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影响CIP清洗效果的因素有：（1）（）（以Re来衡量，从壁面淌下薄液的Re大于200；管道线的Re大于3000；但管道线Re大于30000为效果最好）；（2）（）能（在一定的流量下，（）上升，可提高Re，污物与洗涤溶液的化学反应速度（）；增大污物中（）物质的溶解量）；（3）（）能，主要来自洗液的化学剂。
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You’re a network administer and you issue the command （show port 3/1） on an Ethernet port. To your surprise you notice a non-zero entry in the ’Giants’ column. What could be the cause of this？ （）
A . IEEE 802.1Q
B . IEEE 802.10
C . Misconfigured NIC
D . User configuration
E . All of the above
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用雷诺数判别流态的方法如下：Re≤2000为层流，Re>2000为紊流。
A . 正确
B . 错误
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对于内壁光滑的硬管：当Re＜2320时为层流，Re＞2320时为紊流（）
A . 正确
B . 错误
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对于橡胶软管：当Re＜2000时为层流，Re＞2000时为紊流（）
A . 正确
B . 错误
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用雷诺数判别流态的方法如下：Re≤2100为层流，Re＞2100为紊流。（）
A . 正确
B . 错误
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判定流体流动方式是通过雷诺尔准数（Re）当Re≥4000时，流体流动称为（）
A . 层流
B . 湍流
C . 过渡区流动
D . 滞流
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Any alteration in design would mean re-setting our machines, and the cost of this would be prohibitive___ you could place an order for more than 5,000.
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Le frère de ma mère est le ( ) de mon père.
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You're the only person ______I've ever met ______could do it.
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若Re(p)>1中，ξ（s）没有零点，那么在Re(p) 正确答案： √
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输油管道流态划分的标准是：层流Re≤2000，过渡流2000<Re≤3000，紊流光滑区3000<Re≤Re1，混合摩擦区（）。
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听力原文： I just wanted to say well done for getting that contract. You did a great job and we know it wasn’t easy. What would you say to a celebratory meal？ I know a very good restaurant near here. I’m sure we could get a table for lunch if you’re free.
—You will hear five recordings.
—For each recording, decide what the main reason is for the phone call.
—Write one letter (A—H) next to the number of the recording.
—Do not use any letter more than once.
—After you have listened once, replay each recording.
A booking a table
B cancelling a meeting
C placing an order
D selling something
E offering a lift
F congratulating someone
G checking an address
H making an appointment
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I _____ girlnd you ____ boy.is,reB．m, isC．m,reD．re,reI _____ girlnd you ___ _ boy.is,re B．m, is C．m,re D．re,re
A．is, are
B．am, is
C．am, are
D．are,are
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If you're like me, you're 【C1】______ of big income claims--like the one I just made. I don't blame you. After all, it usually means you're about to be conned into some theoretical business 【C2】______ that "could" work... if you're extremely lucky!
Well now you can say goodbye to those schemes, plug into a thriving ＄ 95 billion industry, and collect six figures from home with no risk, overhead, or employees. I'll even partner with you, 【C3】______ my own money on your success, and 【C4】______ the profits with you 50/50!
And because I respect you, I 【C5】______ for one red cent until you know exactly what this business involves... just give me a couple of minutes to prove everything I've promised so far. Fair enough？
Being a home-based recruiter is simple: you find and introduce qualified job candidates to companies... and collect enormous finder's fees when your candidates are hired. For just one placement, a typical finder's fee is ＄8,000--＄12,000!
Why so much？ By outsourcing this function, companies can 【C6】______ positions more quickly, eliminate salaried HR employees, and slash their 【C7】______ costs (even more necessary in today's economy).
Now let's look at this risk-free business. Your clients may call you a "headhunter", "search firm", or "job 【C8】______ agency". But they all mean the same thing: you're a recruiter. And here's the exciting part:
With just a computer and fax machine, home-based recruiters (like me) scooped up over ＄1 billion last year, working from the comfort of our homes, in our tee shirts!
Since this is a "business 【C9】______ business" profession, you’ll be in daily contact with other professionals. And since most of the simple tasks 【C10】______ in your spare time, you're free to keep your day job while you get started.
【C1】______
A．skeptical
B．skept
C．skepting
D．skepted
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It may be the last book you'll ever buy. And certainly, from a 【C1】______ standpoint, it will be the only book you'll ever need. No, it's not the Bible or some New Age tome 【C2】______ enlightenment--although it would let you carry 【C3】______ both texts simultaneously. It's an electronic book--a 【C4】______ volume that could contain a library of information or, if your tastes run 【C5】______ what's current, every title on today's bestseller 【C6】______ And when you're 【C7】______ with those, you could refill it with new 【C8】______
Convenience is its main 【C9】______ and that means more than simple portability. Because the information is in electronic 【C10】______ , it can be easily manipulated. You could, for instance, make the type larger for easier reading. Or you could make notes in the 【C11】______ with a stylus your observations being 【C12】______ on tiny, removable flash-memory card in the spine.
It is likely that electronic books will come pre-loaded with a 【C13】______ of titles. New titles could be made 【C14】______ through flash-memory cards, for example, internet will be the delivery method of choice. Imagine browsing an online bookstore like www. Amazon. com, corn and downloading a novel 【C15】______ your electronic book via the modem in its spine. 【C16】______ Moby Dick would take about a minute. You could download a few titles, so you'll have a few good reads to choose from while you're relaxing at the beach. If your first choice is not to your 【C17】______ , a new title becomes available 【C18】______ the push of a button.
An electronic book will be 【C19】______ --around ＄ 200 for a basic read-only model to about ＄ 400 for one that would 【C20】______ your margin scribbles. Some hurdles remain, though, before you can take an electric book with you anywhere.
【C1】______
A．practicable
B．feasible
C．workable
D．practical
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Tile media can impact current events. As a graduate student at Berkeley in the 1960s, I re member experiencing the events related to the People's Park that were occurring on campus. Some of these events were given national media coverage in the press and on TV. I found it interesting to compare my impression of what was going on with perceptions obtained from the news media．I could begin to see events of that time feed on news coverage. This also provided me with some healthy insights into the distinctions between these realities.
Electronic media are having a greater impact on the people's lives every day. People gather more and more of their impressions from representations. Television and telephone communications are linking people to a global village, or what one writer calls the electronic city. Consider the information that television brings into your home every day. Consider also the contact you have with others simply by using telephone. These media extend your consciousness and your contact. For example, the video coverage of the 1989 San Francisco earthquake focused on "live action" such as the fires or the rescue efforts. This gave the viewer the impression of total disaster. Television coverage of the Iraqi War also developed an immediacy. CNN reported events as they happened．This coverage was distributed worldwide. Although most people were far away from these events, they developed some perception of these realities.
In 1992, many people watched in horror as riots broke out on a sad Wednesday evening in Los Angeles, seemingly fed by video coverage from helicopters. This event was triggered by the verdict (裁定) in the Rodney King beating. We are now in an age where the public can have access to information that enables it to make its own judgements, and most people, who had seen the video of this beating, could not understand how the jury (陪审团) was able to acquit (宣布……无罪) the policemen involved．Media coverage of events as they occur also provides powerful feedback that influences events. This can have harmful results, as it seemed on that Wednesday night in Los Angeles. By Friday night the public got to see Rodney King on television plea ding, "Can we all get along？" By Saturday, television seemed to provide positive feedback as the Los Angeles riot turned out into a rally for peace. The television showed thousands of people marching with banners and cleaning tools. Because of that, many more people turned out to join the peaceful event they saw unfolding on television. The real healing, of course, will take much longer, but electronic media will continue to be a part of that process.
The best title for the passage is______.
A．The 1992 Los Angeles Riots
B．The Impact of Media on Current Events
C．The 1989 San Francisco Earthquake and the 1992 Los Angeles Riots
D．How Media Cover Events
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- Excuse me, could you show me the way to the nearest post office？- You&39;re welcome. Oh yes! Two blocks away from here at the Green Avenue. You can&39;t miss it.()
对
错
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在差动放大电路中，若射极电阻 RE 越大，则（)，但 RE 也不能太大。
A．Ad越大
B．Ad越小
C．Ac越小
D．KCMRR越小
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当输气管的Re＞Re2时，为阻力平方区When Re＞Re2 of the gas pipe, is the resistance square area； 当输气管的Re1＜re＜re2时，为混合摩擦区when of the gas pipe, it is mixed friction zone； hydraulic smooth＞
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―Could you look after my dog for me while we're away？ ―___________________
A.No， thanks.
B.With pleasure.
C.I'm not afraid.
