具有半月板的关节是（）。 A.髋关节 B.膝关节 C.肩关节 D.肘关节 E.腕关节

（）是根据专家的判断或调查者的主观判断来决定选取的样本

A.简单随机抽样法

B.任意抽样法

C.分层随机抽样法

D.判断抽样法

Border Gateway Protocol(BGP) is inter-autonomous system （71） protocol. BGP is based on a routing method called path vector routing. Distance vector routing is not a good candidate for inter-autonomous system routing because there are occasions on which the route with the smallest （72） count is not the preferred route. For example, we may not want a packet through an autonomous system that is not secure even though it is shortest route. Also, distance vector routing is unstable due to the fact that the routers announce only the number of hop counts to the destination without defining the path that leads to that （73） . A router that receives a distance vector advertisement packet may be fooled if the shortest path is actually calculated through the receiving router itself. Link （74） routing is also not a good candidate for inner-autonomous system routing because an internet is usually too big for this routing method. To use link state routing for the whole internet would require each router to have a huge link state database. It would also take a long time for each router to calculate its routing （75） using the Dijkstra algorism.

74（）

A．status

B．search

C．state

D．research

老师和学生都希望成功，根据你对课文《再塑生命》的理解，你认为莎莉文老师和海仑·凯勒各自取得成功的秘诀是什么？

莎莉文老师：____________________________________

海伦·凯勒：_____________________________________

按照触电防护方式，电气设备分为4类，其中______设备具有双重绝缘和加强绝缘的安全防护措施。

A．0类
B．Ⅰ类
C．Ⅱ类D．Ⅲ类

地榆的薄层色谱鉴别对照品为

A．齐墩果酸
B．熊果酸
C．地榆酸
D．咖啡酸
E．没食子酸