证券公司在进行自营买卖时，其交易方式可以在法规范围内依交易量而自主选择。( )

设N_A为阿伏加德罗常数的数值，下列说法中正确的是

A．标准状况下，11.2L Cl₂和H₂混合气体原子数为2N_A

B．常温下，pH=l的H₂SO₄溶液中含有的H⁺的数目为0.2N_A

C．在含Al³⁺总数为N_A的AlCl₃溶液中，Cl^-总数大于3N_A

D．标准状况下，2.24LCl₂溶于水，转移的电子数目为0.1N_A

系统功能分为通话功能、（）、会议功能、录音功能、维护管理功能。

轻型胎盘早剥有哪些表现（）

A.多见于分娩期，以外出血为主

B. * * 流血

C.轻度腹痛或无腹痛

D. * * 流血量与贫血体征不符

E.胎心多正常

Even though current technologies make the ultimate segmented network impractical, new technologies and products hold the promise of making the concept a reality. Most important of all these new technologies are (66) . The ultimate switched LAN, which is technically possible, now, exhibits the following characteristics:

1. High-speed yet cost-effective switching devices can be implemented on a wide scale, providing dedicated connections for individual users and supporting the aggregate (67) of all networked users.

2. The ability to deploy switching capabilities incrementally into the (68) base. Switching implementations support switching of individual users or groups so that existing users of shared media modules can continue to use the existing equipment until they can justify moving to dedicate switched LAN connections.

3. Support and enhancement of existing routed environments. Switching (69) routint, but rather can be introduced into the network without making any changes to the existing routing equipment or configuration. (70) play a critical role in the integration of switching into existing networks.

（67）（）

A. assigned

B. does not justify

C. replace

D. does not replace

1933年，爱因斯坦离开德国去了哪里？（）

A．瑞士

B．荷兰

C．美国