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问题 选择题

“我们亚洲，河像热血流”是说亚洲的河流众多，奔流不息。下面关于亚洲河流的叙述，正确的是 （ ）

A．发源地中部山地、高原的河流，呈放射状流向太平洋

B．发源于中部山地、高原的河流，呈班射状流向四大洋

C．亚洲第一长河是中国的长江

D．“一江春水向东流”是指亚洲的河流都向东流入东海

答案

答案：C

本题主要考查的是亚洲的相关知识。亚洲的河流主要发源于中部地区，呈放射状流向太平洋、北冰洋和印度洋，亚洲第一长河为长江。“一江春水向东流”是指长江向东流入海。

单项选择题

To compete in today’s fast-paced competitive environment, organizations are increasingly allowing contractors, partners, visitors and guests to access their internal enterprise networks. These users may connect to the network through wired ports in conference rooms or offices, or via wireless access points. In allowing this open access for third parties, LANs become ___19___. Third parties can introduce risk in a variety of ways from connecting with an infected laptop to unauthorized access of network resources to ___20___ activity. For many organizations, however, the operational complexity and costs to ensure safe third party network access have been prohibitive. Fifty-two percent of surveyed CISOs state that they currently use a moat and castle’s security approach, and admit that defenses inside the perimeter are weak. Threats from internal users are also increasingly a cause for security concerns. Employees with malicious intent can launch ___21___ of service attacks or steal ___22___ information by snooping the network. As they access the corporate network, mobile and remote users inadvertently can infect the network with ___23___ and worms acquired from unprotected public networks. Hackers masquerading as internal users can take advantage of weak internal security to gain access to confidential information.

23（）

A．sickness

B．disease

C．germs

D．viruses
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计算题

（14分）航天员在月球表面完成了如下实验：如图所示，在月球表面固定一竖直光滑圆形轨道，在轨道内的最低点，放一可视为质点的小球，当给小球水平初速度v0时，小球刚好能在竖直面内做完整的圆周运动。已知圆形轨道半径为r，月球的半径为R 。若在月球表面上发射一颗环月卫星，求最小发射速度。
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