早稻田的吉祥物是熊，为什么？

科学家在地球轨道外侧发现了一颗绕太阳运行的小行星，经过观测该小行星每隔t时间与地球相遇一次（即距离最近），已知地球绕太阳公转半径是R，周期是T，设地球和小行星都是圆轨道，且在同一个面同向转动，求

（1）太阳的质量

（2）小行星与地球的最近距离．

牛，夏季吸血昆虫活动频繁时大群发病。病牛发热，流泪，流鼻液，流涎，流产，呼吸迫促。部分病牛全身肌肉和四肢关节肿痛致跛行，步态僵硬。该病传播快，发病率高，病死率低，多数病牛在发病2至5天后自愈。据调查，该病在当地流行周期为3至5年。

动物接种试验应选择的实验动物是（）

A、乳兔

B、乳豚鼠

C、乳仓鼠

D、乳大鼠

E、乳猪

[化学--有机化学基础]

下图是以A为主要起始原料得香料M和高分子化合物N的反应流程（部分产物及反应条件已略去）．

（1）写出C中含氧官能团的名称：______、______．

（2）已知D中无支链，写出D的同类别同分异构体结构简式：______．

（3）生成M的化学方程式为______，反应类型为______．

（4）写出由A生成高聚物N的化学方程式：______．

根据短文内容，从下框的A-F选项中选出能概括每一段主题的最佳选项。选项中有一项为多余选项。

A. The general result of a survey.

B. Some specific data about whether people in different areas are appreciated.

C. Being appreciated may promote growth of productivity.

D. In most places people are well-praised.

E. Most people need encouragement but haven't got it.

F. Politeness actually means much to people.

1._____

     It is often said that politeness costs nothing. In fact, frequently hearing the phrase "thank you" or "well

done" means the same to staff as a pay rise, researchers say. Praise and encouragement makes employees

more likely to work hard and stay in their jobs, saving on the cost of finding replacements.

2._____ 

     A third of 1 000 workers surveyed (调查) by consulting firm White Water Strategies (WWS) said they

did not get thanked at all when they did well, and a further third said they were not thanked enough. In both

cases, staff said they felt undervalued, meaning they were less likely to exert (使努力) themselves and were

more likely to look for employment elsewhere.

 3._____ 

     The yearly result is around 5.2 billion in lost productivity from employees who would improve their

performance if they felt more appreciated, WWS claimed. According to the company, praising staff has

the same encouragement as a l percent pay rise, and works out much cheaper for bosses.

4._____

     Three out of four employees said that regular appreciation by their bosses was important to them, but

only a quarter said they were actually given as much praise as they felt they needed. The survey found that

those in blue-collar and manual (体力的) jobs were less likely to be given any recognition for doing well.

5._____

     In regional terms, Scottish staff felt most undervalued. Four out of ten workers said they were never

thanked and eight out of ten said they would like more praise. However, workers in the Northeast are less

impressed by being praised by the boss, for only 69 per cent said they felt the need to be told "well done"

regularly. Older employees and women need the most reassurance, according to psychologist Averil Leimon,

a director of WWS. She said that words of praise did more than create a pleasant place to work-they could

even increase profits.

听证机关组织听证，（）向当事人收取费用。

A.可以；

B.可以不；

C.不得；

D.应当。