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问题 问答题

下列说法中正确的是（　　）

A．太阳内不停地进行聚变，太阳能实质上是核能

B．太阳光将物体晒热是通过做功的方法使物体温度升高

C．地球上各个位置接收太阳能的情况相同

D．在太阳系中，只有地球才可以接收到太阳辐射的能量

答案

A、太阳内不停地进行聚变，太阳能实质上是核能，A正确；

B、太阳光将物体晒热是通过热传递的方法使物体温度升高，B错误；

C、地球上各个位置接收太阳能的情况不同，C错误；

D、太阳是一个球体，所以在太阳系中，其它星球也可以接收到太阳辐射的能量，D错误．

故选A．

单项选择题

某男工从事重件手工锻打作业，每次锻打十余分钟。该作业氧消耗的特点是（）

A.氧需小于氧上限

B.氧需等于氧上限

C.氧需大于氧上限

D.氧债几乎等于氧需

E.氧债大于氧需
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单项选择题

For many people today, reading is no longer relaxation. To keep up their work they must read letters, reports, trade publications, interoffice communications, not to mention newspapers and magazines: a never ending flood of words. In (1) a job or advancing in one, the ability to read and comprehend (2) can mean the difference between success and failure. Yet the unfortunate fact is that most of us are (3) readers. Most of us develop poor reading (4) at an early age, and never get over them. The main deficiency (5) in the actual stuff of language itself—words. Taken individually, words have (6) meaning until they are strung together into phrases, sentences and paragraphs. (7) , however, the untrained reader does not read groups of words. He laboriously reads one word at a time, often regressing to (8) words or passages. Regression, the tendency to look back over (9) you have just read, is a common bad habit in reading. Another habit which (10) down the speed of reading is vocalization—sounding each word either orally or mentally as (11) reads.
To overcome these bad habits, some reading clinics use a device called an (12) , which moves a bar(or curtain) down the page at a predetermined speed. The bar is set at a slightly faster rate (13) the reader finds comfortable, in order to "stretch" him. The accelerator forces the reader to read fast, (14) word by word reading, regression and subvocalization practically impossible. At first (15) is sacrificed for speed. But when you learn to read ideas and concepts, you will not only read faster, (16) your comprehension will improve. Many people have found (17) reading skill drastically improved after some training. (18) Charlie Au, a business manager, for instance. His reading rate was a reasonably good 172words a minute (19) the training; now it is an excellent 1,378 words a minute. He is delighted that how he can (20) a lot more reading material in a short period of time.

A．our
B．your
C．their
D．other
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