若1 mol某气态烃CxHy完全燃烧,需用3molO2,则[ ] A.x=2,

题型:不定项选择题

问题:

若1 mol某气态烃CxHy完全燃烧,需用3molO2,则[     ]

A.x=2,y=2

B.x=2,y=4

C.x=3,y=6

D.x=3,y=8

考点:有机物燃烧耗氧量
题型:不定项选择题

某电场的电场线分布如图所示,以下说法正确的是(  )

A.c点场强大于d点场强

B.a点电势高于b点电势

C.若将一试探电荷+q由a点静止释放,它将沿电场线运动到b点

D.若将一试探电荷+q由a点静止释放,它将做加速运动

题型:不定项选择题

客户甲欲从外汇储蓄账户现钞户上支取USD500.00用于对外付汇,现汇卖出价6.8088,现钞买入价6.7274,请计算可对外付汇金额。()

A、494.02

B、506.05

C、490.02

D、507.05

题型:不定项选择题

某城市热力管道工程,施工单位根据设计单位提供的平面控制网点和城市水准网点按照一定的次序进行了施工定线测量后,用钢尺丈量定位固定支架、补偿器、阀门等的位置。
在热力管道实施焊接前,根据焊接工艺试验结果编写了焊接工艺方案,并按该工艺方案实施焊接。在焊接过程中,按焊接温度规定,先进行预热后焊接,焊接部位的焊渣在焊缝完全冷却后经敲打除去。在焊接质量检验过程中,发现有不合格的焊接部位,.经返修后达到质量要求标准。

不合格的焊接部位,应采取措施进行返修,同一部位焊缝的返修次数不得超过( )次。

A.1

B.2

C.3

D.4

题型:不定项选择题

形成焦炭时,横裂纹多的煤种是()。

A.气煤

B.肥煤

C.贫煤

题型:不定项选择题

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.some
B.a lot
C.little
D.dull

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