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问题 选择题
若方程
x2
n-2
+
y2
n+3
=1表示焦点在y轴上的双曲线，则n的取值范围（　　）
A．n＞2B．n＜-3C．-3＜n＜2D．n＜-3或n＞2
答案

∵方程

x2
n-2
+
y2
n+3
=1表示焦点在y轴上的双曲线，

∴

n+3＞0
n-2＜0
，解得-3＜n＜2．

故选C．

单项选择题

The Internet is a (66) network of networks which interconnects (67) ranging from the simplest personal computers to the most sophisticated mainframes and supercomputers. This network of networks is used for an extraordinary range of purposes long distance collaborations, retrieving free software and documents, (68) library catalogs, (69) in to supercomputers - the list of current Internet activities and (70) is large and the range of possible future applications is as unlimited as our imagination.

A．logging

B．going

C．coming

D．achieving
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填空题

提高全民族的思想道德素质和科学文化素质，培养一代又一代有理想、有道德、有文化、有纪律的公民，是社会主义__________的根本 任务，也是发展_____________的根本任务。
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