试题与答案

向淀粉溶液中加少量稀H2SO4,加热使淀粉水解,为测其水解程度,需要的试剂是 [

题型:不定项选择题

题目:

向淀粉溶液中加少量稀H2SO4,加热使淀粉水解,为测其水解程度,需要的试剂是

[      ]

①NaOH溶液 ②银氨溶液 ③新制的Cu(OH)2悬浊液 ④碘水

A.④

B.②④

C.①③④

D.③④

答案:

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题型:单项选择题


Passage One

Internet piracy refers to the use of the Internet for illegally copying or distributing unauthorized software. In these cases the Internet is the medium for advertising, offering, acquiring, or distributing pirated software.
The Business Software Alliance, a software industry trade association, estimates that there are 840 000 Internet sites selling illegal software as genuine product. Many consumers Who acquire software over the Internet never receive the programs they paid for. Others are not able to get their money back if they discover that the software they acquired is counterfeit. Disreputable Internet businesses often quickly vanish, leaving behind hundreds of dissatisfied consumers.
The ease of creating a Website and then advertising and distributing software through the Internet has increased sales of pirated software passed off by seemingly legitimate businesses. Plus, the explosive growth of e-commerce, combined with anonymity (匿名) and unlimited volume, have made it even easier for criminals to sell counterfeit (伪造的) software online.
Illegal online businesses often have professional-looking Internet sites that could fool even the smartest consumer. Distinguishing counterfeit software on the Internet is understandably difficult because consumers can’t visually examine the product for physical Warnings on the hard ware, or see the person from whom they’re buying.
Pirated software can often contain viruses with the potential to damage both individual com puters or entire networks. Viruses can and do cause data loss, which would be devastating to most companies. When using unlicensed software, you are not eligible for technical support from the software publisher. If you have a technical issue in need of resolution, oftentimes a work stopping issue, you are out of luck. In addition, product upgrades (升级)—less expensive up grades of existing products—are not available to you.
Based on Business Software Alliance estimates, the current loss of jobs, wages, and critical investments in software and technology innovation worldwide due to piracy so far this year is estimated at: $11 326 675 282.
"Software piracy continues unabated (不减弱的), robbing the industry of thousands of jobs, billions in wages, tax revenues and critical investments in new technologies," according to Robert Holleyman, president and CEO, Business Software Alliance.

Which of the following harms of pirated software is NOT mentioned in the passage

A.It often contains devastating viruses.

B.Buyers are not eligible for technological support from the software publisher.

C.It causes huge loses of tax revenues.

D.It may cause incompatibility (不兼容) between programs that normally function together.

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