在常温常压下，将下列各组气体，等体积混合于等体积的容器中，并立即倒立于盛有水的水

Each machine supporting TCP has a TCP transport entity, either a library procedure, a user process, or part of the kernel. In all case, it manages TCP streams and（）to the IP layer. A TCP（）accepts user data streams from local process, breaks them into pieces not exceeding 64KB, and sends each piece as a separate IP（）. When datagrams containing TCP data arrive at a machine, they are given to the TCP entity, which reconstructs the original byte streams.

The IP layer gives no guarantee that datagrams will be delivered properly, so it is up to TCP to time out and（）them as need be. Datagmms do arrive may well do so in the wrong order, it is also up to TCP to（）them into messages in the proper sequence.

so it is up to TCP to time out and（）them as need be.

A．reassemble

B．reduce

C．re-create

D．retransmit

β受体阻滞剂应首选用于（　　）

A．扩张型心肌病并发心力衰竭

B．风湿性心脏病二尖辦狭窄并发心力衰竭

C．急性病毒性心肌炎并发心力衰竭

D．肺源性心脏病并发心力衰竭

E．冠心病心房颤动并发心力衰竭

我国历史上的三部炮制专著是（）

A.《雷公炮炙论》

B.《本草纲目》

C.《炮炙大法》

D.《修事指南》

E.《本草蒙筌》

--There will be an English film _____ the evening of September 1^st.

--No, it is ____the afternoon.

A．on, on

B．on, in

C．in, on

D．in, in

消息摘要算法MD5(Message Digest)是一种常用的Hash函数。MD5算法以一个任意长的数据块作为输入，其输出为一个______比特的消息摘要。

A) 128
B) 160
C) 256
D) 512