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问题 选择题

下列叙述正确的是     [ ]

A．糖类、油脂、蛋白质和DNA都是提供人体能量的重要物质基础    

B．塑料管材、奶瓶、食物保鲜膜、大棚塑料薄膜等主要材料是聚氯乙烯    

C．SO2、NO2、NO、氟氯烃、CO2等均是造成大气污染的重要物质    

D．葡萄糖能和银氨溶液及新制的Cu(OH)2溶液反应，果糖也能

答案

答案：D

单项选择题

Questions 63 TO 67 are based on the following passage:(10分)　　Television,the modern wonder of electronics,brings the world into your own home in sight and sound.And the word‘television’means seeing far.Television works in much the same way as radio.In radio,sound is changed into electromagnetic waves which are sent through the air.Experiments leading to modern television took place more than a hundred years ago.By the 1920s inventors and researchers had turned,the early theories into working models.Yet it took another thirty years for TV to become industry. The influence of TV on the life of people is incalculable:it can influence their thoughts and their way of life.It can also add to their store of knowledge.Educational TV stations offer teaching in various subjects.Some hospitals use TV for medical students to get close-up views of operations. At first television programs were broadcast in black-and-white.With the development of science and technology,the problem of how to telecast them in full color was solved and by the middle 1960s the national networks were broadcasting most of their programs in color. The programs that people watch are not only local and national ones.Since the launching of the first communications satellite,more and more programs are telecast“live”from all over the world. People in San Francisco were able to watch the 1964 Olympic Games in Tokyo.And live telecasts now come from outer space.In 1969,the first astronauts to land on the moon televised their historic “moon walk”to viewers on the earth.Since then,astronauts have regularly sent telecast to the earth.

The launching of communications satellites made it possible fro people in San Francisco to ______.

A．get close-up views of operations

B．store knowledge

C．watch the 1964 Olympic Games in Tokyo

D．watch national programs
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单项选择题

薄壁灌注法填料法是从堵头4小孔中把（）加入。

A.水

B.机油

C.沙

D.石蜡
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