正常工作的起重机，按有关标准的要求每（）进行一次试验校检。A、半年  B、一年  C

阅读下面短文，从短文后所给各题的四个选项中，选择最佳选项。

        "Dreams may be more important than sleep. We all need to dream." some scientists say. 

        Dreams take up about one quarter of our sleeping time. People have several dreams each night. Dreams

are like short films.They are usually in colour. Some dreams are like old films.They come to us over and over

again. That may be because the dreamer is worrying about something. Dreaming may be a way of trying to find

an answer.

        Some people get new ideas about their work from dreams. They may have been thinking about their work

all day. These thoughts can be carried over into dreams. 

        Sometimes we wake up with a good feeling from a dream. But often we can't remember the dream.

Dreams can disappear quickly from memory.

        Too much dreaming can be harmful. The more we sleep, the longer we dream. The mind is hard at work

when we dream. This is why we may have a long sleep but we feel tired when we wake up.

1. If Jack slept eight hours last night, there was about              dream in the night. [ ]

A. a two-hour

B. a one-hour

C. a one-quarter

D. an eight-hour

2. Why do some people often dream about their work? [ ]

A. Because they are happy in the daytime.

B. Because they are not interested in their work.

C. Because they may be this thinking about their work all day.

D. Because they have too much work to do.

3. The main idea of the passage is that             . [ ]

A. what a dream is

B. people like to sleep

C. dreams are like films

D. we always remember dreams

若已定义的函数有返回值，则以下关于该函数调用的叙述中错误的是

A．函数调用可以作为独立的语句存在

B．函数调用可以作为一个函数的实参

C．函数调用可以出现在表达式中

D．函数调用可以作为一个函数的形参

Gerhardt法只能检出的酮体成分是（）
Rothera法对哪种酮体成分不反应（）

A.丙酮

B.乙酰乙酸

C.β-羟丁酸

D.戊酮

E.α-羟丁酸

冰袋降温的主要原理是增加()。

A.对流散热

B.传导散热

C.辐射散热

D.蒸发散热

E.不感蒸发

下列哪一项不属于民间音乐？（）

A.民间歌曲

B.宫廷音乐

C.民间歌舞

D.说唱音乐