测距机的编码电路应具备”高斯”波形产生的功能。高斯波形是用（）方法产生的。 A.RO

解放前，中国经常发生各种灾荒。每一次大的灾荒死亡的人数，常常不低于一次战争。新中国成立后，尽管也多次发生大规模空前的旱灾和水灾，但因灾害死亡的人数却很少。由此可见( )

A．解放前，国民党政府不注重对灾民的救助

B．解放后，科技的进步，使人们更有办法应对突然袭来的灾害

C．解放后，医疗条件大幅度地改善和提高了

D．新中国成立后优越的政治制度，使人民的抗灾能力大大增强了

阅读理解。

                                                                   A Lucky Thing

     About sixty years ago, a child named Borty was playing one day with a group of naughty boys. When

they were playing happily, an incident happened. An elder child picked up Borty and threw him into the sky.

When Borty fell down, the big child did not catch him but rather let him fall on the ground. As a result, Borty's

leg broke.

     He had to wear heavy plaster while lying in bed for several months. The worst thing was that his leg bone

did not heal. It was a terrible thing to a little child. Little Borty screamed in pain and fear.

     This was a tragedy, but now Borty had a new idea that he was now one of the most famous writers in

the world. Maybe you are not familiar with the name of Borty, But when I mention the name Wells, you must

know it. Maybe you have read some books of his. He wrote more than 75 books. Wells thought that breaking

his leg was a lucky thing for him. It made him have to stay home for one year. In the year he read many books,

because he had nothing to do except that. It made him very interested in literature. He became enlightened by

these books. So his staying home was a turning point for him. Later he became the writer in the world whose

income was highest.

1. When was Borty hurt? 

    ___________________________________________________

2. What was wrong with Borty's leg? 

    ___________________________________________________

3. He had to stay in bed for several months, didn't he? 

    ___________________________________________________

4. What was a turning point for Borty? 

    ___________________________________________________

5. Was Borty a famous reader or a famous writer? 

    ___________________________________________________

学前儿童科学教育评价资料的收集方法主要有观察分析法、问卷调查法和（）。

金融债券的招投标发行通过证券交易所债券发行系统进行。（）

如右图所示，人拉着旅行箱，拉力为F且与水平方向成α角，则人拉着旅行箱前进位移S的过程，拉力做的功为（　　）

A．FSsinα

B．FScosα

C．FStanα

D．FScotα