下列语句中，正确的个数为（ ） ①在Rt△ABC中，∠A+∠B=90°，则sin

下列说法错误的是（　　）

A．用肥皂水区分硬水和软水

B．用水区分硝酸铵和氢氧化钠固体

C．用酚酞试液可区分盐酸和食盐水

D．用燃烧的方法可区分聚乙烯和聚氯乙烯

图描绘的是我国古代的劳动生产场景，图中题诗为康熙帝所作。与这一劳动生产场景相关的行业是（  ）

A．棉纺织业

B．麻纺织业

C．造纸业

D．丝织业

阅读理解。

     Thirteen vehicles(车辆)lined up last March to race across the Mojave Desert, seeking a million

in prize money. To win, they had to finish the 142-mile race in less than 10 hours. Teams and

watchers knew there might be no winner at all, because these vehicles were missing a key part-drivers.

     DARPA, the Defense Advanced Research Projects Agency, organized the race as part of a push

to develop robotic vehicles for future battlefields. But the Grand Challenge, as it was called, just

proved how difficult it is to get a car to speed across an unfamiliar desert without human guidance.

One had its brake locked up in the starting area. Another began by throwing itself onto a wall. Another

got tied up by bushes near the road after 1.9 miles.

     One turned upside down. One took off in entirely the wrong direction and had to be disabled by

remote (远距离的) control. One went a little more than a mile and rushed into a fence; another

managed to go for six miles but stuck on a rock. The "winner," if there was any, reached 7.8 miles

before it ran into a long , narrow hole , and the front wheels caught fire.

"You get a lot of respect for natural abilities of the living things," says Reinhold Behringer, who helped

design two of the car-size vehicles for a company called Sci-Autonics. "Even ants  can do all these

tasks effortlessly. It's very hard for us to put these abilities into our machines."

     The robotic vehicles, though with necessary modern equipment such as advanced computers and

GPS guidance, had trouble figuring out fast enough the blocks ahead that a two-year-old human

recognizes immediately, Sure, that very young child, who has just only learned to walk, may not think

to wipe apple juice off her face, but she already knows that when there's a cookie in the kitchen she

has to climb up the table, and that when she gets to the cookie it will taste good. She is more advanced,

even months old, than any machine humans have designed.

1. Watchers doubted if any of the vehicles could finish the race because      __.

A. they did not have any human guidance

B. the road was not familiar to the drivers

C. the distance was too long for the vehicles

D. the prize money was unattractive to the drivers

2. DARPA organized the race in order to        .

A. raise money for producing more robotic vehicles

B. push the development of vehicle industry

C. train more people to drive in the desert

D. improve the vehicles for future wars

3. From the passage we know "robotic vehicles" are a kind of machines that       _.

A. can do effortlessly whatever tasks living things can

B. can take part in a race across 142 miles with a time limit

C. can show off their ability to turn themselves upside down

D. can move from place to place without being driven by human beings

4. In the race , the greatest distance one robotic vehicle covered was        .

A. about eight miles  

B. six miles  

C. almost two miles

D. about one mile

5. In the last paragraph , the writer implies that there is a long way to go        .

A. for a robotic vehicle to finish a 142-mile race without any difficulties

B. for a little child who has just learned to walk to reach the cookie on the table

C. for a robotic vehicle to deal with a simple problem that a little child can solve

D. for a little child to understand the importance of wiping apple juice off its face

该病人的中医诊断是：

A．便秘

B．腹痛

C．腹胀

D．泄泻

E．以上都不是

设计联动夹紧机构的要点是什么？