积极的人在忧患中发现机会，消极的人在机会中发现忧患。谈谈你对这句话的理解。

(66) is used to ensure the confidentiality, integrity and authenticity of the two end points in the private network. (67) , an application-layer protocol, authenticates each peer in an IPsec transaction. IKE negotiates security policy, determining which algorithm may be used to set up the tunnel. It also handles the exchange of session keys used for that one transaction.
Networks that use (68) to secure data traffic can automatically authenticate devices by using (69) , which verify the identities of the two users who are sending information back and forth. IPsec can be ideal way to secure data in large networks that require secure connections among many devices.
Users deploying IPsec can (70) their network infrastructure without affecting the applications on individual computer. The protocol suite is available as a software-only upgrade to the network infrastructure. This alows security to be implemented without costly changes to each computer. Most important, IPsec allows interoperability among different network devices, PCs and other computing systems.

A．secure

B．relation

C．script

D．strict

读下列四幅地形剖面图，分析回答：

（1）上述哪一幅图能正确表示我国地势变化？______

（2）由此概括出我国地势的主要特点______

（3）这种地势特征对我国河流流向有哪些影响？______．

肝功能不全者忌用（）

A.甘草

B.麻黄

C.黄药子

D.马兜铃

E.麦芽

蚕农在蚕花娘娘生日时做米粉团子呈供，这种团子叫做“茧圆”。

据国家统计局数据显示，2002年我国国内生产总值达到102398亿元，比2001年增长8%。与2001年相比，第一产业达14883亿元，增长2.9%；第二产业增长9.9%，达到52982亿元；第三产业增长率达到7.3%。据统计，去年工业增加值45935亿元，增长10.2%；固定资产投资43202亿元，增长16.1%；社会消费品零售总额40911亿元，增长8.8%。2002年，城乡居民收入持续增长，城镇居民人均可支配收入77039己，农村居民人均纯收入2476元，分别增长13.4%和4.8%。

2001年我国城镇居民人均可支配收入是农村人均纯收入的多少倍( )

A．3.1倍

B．2.1倍

C．2.9倍

D．1.9倍