6502电气集中单独操纵道岔采用双按钮制，即按下（）外，还同时按下道岔总定位按钮或道

After a day’s hard work, we need some sleep. During the sleep, the fatigue (疲劳) of the body disappears and recuperation (恢复) begins. The tired mind gathers new energy, and the memory improves: Some adults require little sleep; others need eight to ten hours in every twenty-four hours. Infants (婴儿) sleep sixteen to eighteen hours dally, the amount gradually diminishing as they grow older. Young students may need twelve hours; university students may need ten. A worker with a physically demanding job may also need ten, whereas an executive working under great pressure may manage on six to eight. Many famous people have little sleep. Napoleon Bonaparte, Thomas Edison and Charles Darwin apparently averaged only four to six hours a night.

Whatever your individual need, you can be sure that by the age of thirty you will have slept for a total of more than twelve years. By that age you will also have developed a sleep routine: a favorite hour, a-favorite bed, a favorite position, and a rule you need to follow in order to rest comfortably.

Investigators have tried to find out how long a person can go without sleep. Several people have reached more than 115 hours—nearly five days. Whatever the limit, it is absolute. Animals that kept awake for from five to eight days have died of exhaustion. The limit for human beings is probably about a week.

From the amount of sleep Napoleon, Edison, and Darwin required, we can conclude（）

A. that they were famous

B. that they were executives

C. that they were intelligent

D. None of the above

(9分)写出下列变化的化学方程式，并注明反应条件和反应类型。

(1)乙烯和HCl反应的化学方程式                     ，反应类型为    

(2)苯和浓HNO₃反应的化学方程式                         ，反应类型为    

(3)苯和溴反应的化学方程式                             ，反应类型为    

患儿，男，2岁。出生后即有青紫，发育落后，有杵状指，喜欢蹲踞，临床诊断为法洛四联症，15分钟前突然发生昏厥来院就诊。

首先考虑该患儿发生的情况是（）

A.脑血栓

B.癫痫

C.急性脑缺氧发作

D.心力衰竭

E.低钙惊厥

物流信息平台最重要的作用是能整合个物流信息系统的（），完成各系统之间的（）实现（）

下列关于植物激素的叙述中，错误的是（）

A.赤霉素能促进细胞生长

B.细胞分裂素能促进细胞分裂

C.乙烯是一种气体激素，能促进果实的发育与成熟

D.脱落酸能抑制细胞分裂