项目可行性研究的前提的基础是( )。A．市场调查和预测研究 B．建设条件研究 C．

按照逻辑结构分类，结构可以分为线性结构和非线性结构，栈属于______。

患者男，78岁。慢性肺源性心脏病顽固性心力衰竭，经抗感染及强心利尿治疗效果不佳，进一步采取的措施是（）

A.加大强心剂剂量

B.加大利尿药剂量

C.应用激素治疗

D.应用血管扩张剂

E.呼吸机辅助通气

在题后横线上简要说明下列操作可能造成不良后果．

（1）酒精灯熄灭后未盖灯帽______．

（2）给试管中的液体加热时，大拇指压在试管夹的短柄上______．

（3）用试管刷刷洗试管时，用力过猛______．

（4）加热试管里的液体时试管口对着人______．

In the following essay, each blank has four choices. Choose the most suitable one from the four choices and write down in the answer sheet. There are two types of key technology: private key and public key. Private-key encryption methods are called (71) ciphers, information is encrypted with (72) both the sender and receiver hold privately. Public-key encryption methods are called (73) ciphers, (74) created for each user, encryption key and deception key are (75)

A．same

B．different

C．difference

D．some

不整合常分为（）种。

A.二

B.三

C.四

D.五