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问题 单项选择题

约翰于1995年10月20日就某一项发明在德国申请了专利，1996年9月30日，就该发明又向中国专利局提出了专利申请，并申请了优先权，后约翰的发明分别在德国和中国于1997年12月3日、1998年8月15日被授予专利。据此，约翰的发明专利权在中国的有效期应到（）

A.2012年12月31日

B.2016年9月30日

C.2011年8月15日

D.2015年10月20日

答案

参考答案：B

选择题

下列有关菌落的描述正确的是  [ ]

A．每个菌落都由大量不同种细菌组成

B．一个菌落是由一个细菌细胞形成的

C．细菌的菌落呈绒毛状，絮状或蜘蛛状

D．从菌落的形态，大小和颜色，可以大致区分细菌和真菌，以及它们的种类
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填空题

Crash-Prone The Solution Could Be Windows XP;
But does It Make Sense to Upgrade Your Operating System


You can hardly turn on the television or click on a Web page without seeing a colorful ad for Microsoft’s new Windows XP operating system, which launched on Oct. 25.
So, now that the long-awaited XP is here, what are you going to do about it Should you upgrade, and if you do, how hard is it and what are the potential drawbacks The decision is pretty easy if you really need a whole new Windows PC. They all come with XP preloaded, and in my tests of a few such models, they seemed to work well. I’m writing this on my own new personal computer, a Dell that came preloaded with Windows XP, and it worked great right out of the box.
The only downside is that if you’re keeping older printers, scanners and other peripherals, you may have to download new "drivers" — the small programs that allow a PC and a peripheral to interact. XP contains many of the drivers for recent-model printers and the like, sparing you from even digging out the disks that came with them. But if you have older equipment, you may have to download new drivers, because the original software that came with the hardware might not work with Windows XP.
It’s harder to decide what to do about XP if you have a PC that doesn’t need replacing. If you’re happy with the way things are working, don’t upgrade. It’s never a trivial thing to change operating systems, and you shouldn’t do it without a reason.
However, there are two big limitations in prior versions of Windows that XP does fix, and that might make an upgrade worthwhile. These are stability — that is, the ability not to crash, or at least to do so rarely — and compatibility. Windows 98 and Windows ME, the previous consumer versions, had wide compatibility with consumer software and peripherals, but lousy stability. Windows 2000, the prior business version, had great stability, but limited compatibility with consumer software and add-on hardware.
Windows XP is designed to combine the stability of Windows 2000 (with which it shares underlying code) with the compatibility of Windows 98 and Windows ME, and in my experience, it does a good job at that. So if you need more reliability or compatibility than your current version of Windows supplies, an upgrade may be in order.
But there’s a catch. Microsoft says that an XP upgrade will really be sensible only if your PC is two years old or less — built after 1999. And you need at least a 300MHz processor and 128 megabytes of memory, though I recommend at least 192MB, and 256MB is even better. Also, you’ll need a roomy hard disk — Windows XP alone will suck up 1.5 gigabytes.
So there are only a limited number of PCs for which upgrading makes sense, and you may have to invest in beefing yours up first.
Not only that, but you must have Windows 98, Windows ME or Windows 2000 on your current system to upgrade. If you have Windows 95 and somehow still have a new enough machine to qualify, you have to buy a very expensive, "full" version of Windows XP, basically wipe out your whole hard disk and start from scratch with XP, losing all your installed programs and settings.
If you’re good to go, you next have to decide which upgrade version of XP is right for you — the $99 Home Edition or the $199 Professional. The differences between them are surprisingly small, and 95 percent of home and small-business users will be fine with the home version. Buy the pro version only if you are running more than a modest network or need special security features.
Note that if you have Windows 2000, or NT 4.0, you can upgrade only to Windows XP Professional, not the Home Edition. If you have Windows 98 or ME, you can choose either flavor of XP.
In my tests, which included five PCs running all the main older versions; the Windows XP upgrades, both home and pro, went very smoothly.
The process took about an hour in each case, and the installation software was friendly and clear in its instructions and progress reports.

Prior versions of Windows are inferior to Windows XP in that ______.
A. the former is weaker in either stability or compatibility
B. the former is weaker in both stability and compatibility
C. the former is more expensive
D. the former is less colorful
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