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问题 选择题

下列叙述错误的是(  )

A．原子由原子核和电子构成

B．分子总是不断运动

C．干冰中的分子间有间隔

D．原子失去电子后变成阴离子

答案

答案：D

题目分析：A、原子由原子核和核外电子构成，说法正确；

B、分子总是不断运动的，说法正确；

C、干冰是由二氧化碳分子构成的，二氧化碳分子之间存在间隔，说法正确；

D、原子不显电性，电子带负电，原子失去电子后，显正电，为阳离子，故D说法错误；

故选D。

点评：原子失电子形成阳离子，原子得电子形成阴离子。

单项选择题 A1型题

黄芪的主要有效成分是（）

A.生物碱

B.黄芪多糖和黄芪皂苷

C.微量元素

D.维生素

E.纤维素和鞣质
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单项选择题

As the name implies, CTI (Computer-Telephone-Integration) is the fusing of telephone operations with those performed by a computer. CTI has actually been around for a good two decades. Until recently, it required users to (36) a good deal of knowledge about telephone interconnect processes as well as networking and database programming to (37) even the most rudimentary tasks. These two skill sets are rarely possessed by the same individual.

But today CTI has gone client/server. Microsoft corp. has included its client-side Telephony API (TAPI) with every copy of Windows 95. The company’s service-side TAPI is now available for Windows NT. There are many telephony (38) that turn the interconnect portion of a CTI (39) into standard data programming, and low-cost, easy -to- create telephony is born. Better yet, many of these (38) are Visual Basic add-ons. CTI is also subject to all the cost benefits of cheaper, PC-based hardware.

The two portions of CTI are (40)

（40）是（）

A.interconnectionandTelephonytoolkits

B.interconnectionandVisualBasicall-ones

C.interconnectionandprogramming

D.networkinganddatabaseprogramming
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