上下锅筒临时固定时，不得在锅筒上（）或引弧。A、绑扎 B、放吊环 C、焊接 D、找中

零点极点

两种盐的固体混合物：①加热时有气体产生，②加水溶解时有沉淀生成，且沉淀溶于稀盐酸．满足上述条件的混合物是（　　）

A．BaCl₂和（NH₄）₂S0₄

B．AgNO₃和NH₄Cl

C．FeCl₃和NaHCO₃

D．KCl和Na₂CO₃

BGP is an inter-autonomous system routing protocol; it is designed to be used between multiple autonomous ( ) . BGP assumes that routing within an autonomous system is done by an intra-autonomous system routing protocol.BGP does not make any assumptions about intra-autonomous system （） protocols employed by the various autonomous systems. Specifically， BGP does not require all autonomous systems to run the same intra-autonomous system routing protocol.

BGP is a real inter-autonomous system routing protocol. It imposes no constraints on the underlying Internet topology. The information exchanged via BGP is sufficient to construct a graph of autonomous systems connectivity from which routing loops may be pruned and some routing ( ) decisions at the autonomous system level may be enforced.

The key feature of the protocol is the notion of Path Attributes. This feature provides BGP with flexibility and expandability. Path （） are partitioned into well-known and optional. The provision for optional attributes allows experimentation that may involve a group of BGP （） without affecting the rest of the Internet.   New optional attributes can be added to the protocol in much the same fashion as new options are added to the Telnet protocol， for instance.

BGP is an inter-autonomous system routing protocol; it is designed to be used between multiple autonomous （） .

A．routers  

B．systems

C．computers

D．sources

天然水及饮用水中主要含有六价硒或四价硒，水样加酸与不加酸保存对测定结果影响不大。

在工程项目索赔中，承包商向业主的索赔不包括（）。

A．不利的自然条件与人为障碍引起的索赔

B．工期延期的费用索赔

C．物价上涨引起的索赔

D．施工缺陷索赔