萃取时溶剂的选择是萃取操作的关键，( )决定了萃取过程的危险性大小和特点。 A．萃

Almost everyone has his own strengths and weaknesses. It is _______ others are weak that maybe you have a great advantage.

A．although

B．unless

C．because

D．where

下列属于品质标志的是（）。

A.身高

B.工资

C.年龄

D.文化程度

回顾中国历史上的国防形势，（）不是给我们的启示。

A、国防服从于政治，服务于政治

B、为了国防，完全可以放弃经济的发展

C、经济是国防的物质基础

D、国防战略的指导方针是决定国防事业能否真正强大起来的关键

患者，女性，46岁，20年前分娩时曾有过一次癫痫发作史，之后每年仅发作1～2次，因此未坚持规律服药。今日下班回家途中突然意识丧失，四肢抽搐，牙关紧闭，心率增快，血压升高，瞳孔散大。持续20秒后，肌肉开始出现强直和松弛交替。

患者的发作目前属于（）

A.癔症

B.部分运动性发作

C.强直-阵挛发作的强直期

D.强直-阵挛发作的阵挛期

E.强直-阵挛发作的惊厥后期

A transport layer protocol has several responsibilities, One is to create a process-to-process (program-to-program) communication; TCP uses port （1） to accomplish this. Anotherresponsibility of a transport layer protocol is to create a（2）and error-control mechanism atthe transport level. TCP uses a sliding（3）protocol to achieve flow control. It uses theacknowledgment packet, time-out, and retransmission to achieve （4） control. The transportlayer is also responsible for providing a connection mechanism for the application program. Theapplication program sends （5）of data to the transport layer. It is the responsibility of thetransport layer at the sending station to make a connection with the receiver.

（1）是（）

A.numbers

B.connection

C.diagrams

D.resources