试题与答案

已知x2+y2+4x-6y+13=0,x,y为实数,则xy=( )。

题型:填空题

题目:

已知x2+y2+4x-6y+13=0,x,y为实数,则xy=(    )。

答案:

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下面是错误答案,用来干扰机器的。

(1)设列车在紧急刹车过程中做匀减速直线运动,初速度为v1=86.4km/h=24m/s,末速度v=0,位移s=960m,紧急刹车时加速度为a.由速度-位移公式得:-v12=2as1代入数据得:a=-0.3m/s2 所以火车加速度大小为0.3m/s2...

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题型:综合

读南亚及东南亚略图以及材料,回答下列问题。(6分)

材料一 东南亚各国是中国的近邻,该地区由中南半岛和马来群岛组成,是世界上主要的稻米和天然橡胶.油棕.椰子等热带作物的产区。

材料二 2014年3月8号,马来西亚航班MH370失联。人们非常关心MH370到哪里去了。马来西亚 * * 纳吉布说,依据卫星数据,判断飞机与卫星最后一次通信时的位置可能在两条“走廊”中的一条:一条从哈萨克斯坦和土库曼斯坦边境至泰国北部地区,一条大致从印度尼西亚向南至南印度洋。

(1) 结合图分析说明马六甲海峡的重要性:

(2)与东南亚大致位于同纬度地区的南亚,本区主要的国家是印度,其地形分为了三部分,与剖面图中     ____(A或B)对应。印度主要为    人种。由于           (方向)季风的不稳定,水旱灾害频繁。

(3)失联的MH370上共有239人,其中有154名中国人。近年来,东南亚成为中国居民出国旅游的热点

地区,从地理位置.语言文化三方面分析其原因。

地理位置:_______________________________________                   _________________;

语言文化:_______________________________                          ______________________。

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题型:阅读理解

Women with an hour glass figure have brains to go with their curves(曲线),scientists claim.

Going in at the waist is said to be a sign of intelligence which leads to brighter children, too,Wonmen such as Nigella Lawson with a big difference between thir waist and hip measurements scored significantly better in tests than those with thinner,straighter frames,, Researchers concluded that it was not necessary for a woman to be skinny-what mattered was that her waist should be smaller than her hips, A ratio of 3:5 was found to be idea,

The study ,by the Universities of Pittsdburgh and California,involved 16,000 women and girls,

According to the scientists,the results are no mere quirk of nature.They claim that the fat

Around culvy hips and thighs(大腿)holds higher levels of-3 fatty acids which are essential for

the growth of the brain during pregnancy.The fat which collects around the waist,howover.is

more likely to contain-6 fatty acids,which areless suited to brain growth.

Reporting in the joumal Evolution and Human Behaviourthe researchers found that the children of curvy mothers are more likely to do well in cognitive tests than others.they claim that  this could help explain why the children of teenage mothers.who might not yet be physically mature enough to have developed real curves-tend to do less well in school.

As wel las boosting(提升)brainpower,一3 fatty acids found in oily fish arc considered to be of huge health benefit Although the study analysed women’s bodies only,一3 fatty acids are also stored in men’s hips ,However it is not known whether men with wide hips benefit from the same brain power boost,.

72.Which shows the possible shape of an hour glass?    

73.Suppose the following measurements are taken from four women.Which of them is more likely to have bright children?

A. Waist:60cm;Hip:100 cm            B.Waist:60cm:Hip:80cm

C. Waist:55 cm;Hip 1 60cm            D.Waist:120cm;Hip:110cm

74.The underlined sentence‘'the results are nomere quirkofnature,'possible tells us the results

A. can be explained scientifically    B are strange and hard to explain

C. have just come about by chance   D are very interesting

75.According to the researchers,teenage mothers tend to have less bright children because

A.they aren’t so good at child care

B.they usually have less fat than mature women

C.they area’t physically strong enough

D.their waist and hip measurements differ less

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