半自动埋弧焊机主要由（）组成。 A．导轨 B．控制箱 C．送丝机构 D．机头

下列哪种疾病不出现主动脉根部不扩张表现（）

A.法洛四联征

B.Marfan综合征

C.梅毒性心脏病

D.主动脉瓣狭窄

E.心内膜纤维弹性组织增生症

在写有1～10的卡片中任意抽一张，抽到质数的可能性是______%．

第二部分：阅读理解（共20小题；每小题2分，满分40分）

阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项，并在答题卡上将该项涂黑。

A

More and more often we heard of people talking about Karaoke (卡拉OK). But what on earth it is about still remains a question for many people. Karaoke is a sort of acoustic (听觉的) equipment which was invented in Japan around the middle of the 1970's. It means "a band without people" in Japanese. In fact, it is just a music tape without words. This equipment first appeared in some public houses and snack bars, and mainly for the customers to enjoy themselves. Most of the music in Karaoke was popular music. Therefore, at times,  when anyone felt like it, he might sing songs to the accompaniment (陪伴) of the music that came from the equipment. Shortly after its invention, Karaoke was spread to the whole world. It was introduced to China and was welcomed by many people. Although you are not a good singer, or even sometimes you may sing out of tune, you can always enjoy yourself by singing Karaoke.

56. In this passage "band" means "group of persons ________."

A. who play games on the sports ground   

B. who play music together

C. living in the same neighborhood

D. doing things together under a leader and with a common purpose

57. Karaoke is just a ______.

A. cassette tape with only music      B. cassette tape recorder

C. band from Japan               D. voice recording equipment

58. People went to public houses and snack bars ______when Karaoke appeared.

A. to have a good time                     B. to have something to drink

C. to get something to eat                 D. to buy the equipment

59. Karaoke was spread to the whole world ________.

A. as soon as it was invented              B. long before

C. not long after it was invented           D. before long

60. The main idea of this passage is ______.

A. all persons like to play Karaoke        

B. to introduce Karaoke to the people

C. Karaoke is a wonderful equipment

D. Karaoke is used everywhere including snack bars

在下列建筑安装工程费用构成中，应列入直接费的是（ ）。

A．施工机械使用费

B．仪器仪表使用费

C．检验试验费

D．工具、用具使用费

球人口第一次达到10亿，用了几年？