满分5 >
初中数学试题 >
2007年4月,全国铁路进行了第六次大提速,共改造约6 000千米的提速线路,总...
2007年4月,全国铁路进行了第六次大提速,共改造约6 000千米的提速线路,总投资约296亿元人民币,那么,平均每千米提速线路的投资约 亿元人民币.(用科学记数法表示,并保留两个有效数字).
考点分析:
相关试题推荐
一个圆锥的高为
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022161600200089739/SYS201310221616002000897011_ST/0.png)
,侧面展开图是半圆,则圆锥的侧面积是( )
A.9π
B.18π
C.27π
D.39π
查看答案
若关于x的一元二次方程x
2+kx+4k
2-3=0的两个实数根分别是x
1,x
2,且满足x
1+x
2=x
1•x
2.则k的值为( )
A.-1或
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022161600200089739/SYS201310221616002000897010_ST/0.png)
B.-1
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022161600200089739/SYS201310221616002000897010_ST/1.png)
D.不存在
查看答案
在下图右侧的四个三角形中,不能由△ABC经过旋转或平移得到的是( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022161600200089739/SYS201310221616002000897009_ST/images0.png)
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022161600200089739/SYS201310221616002000897009_ST/images1.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022161600200089739/SYS201310221616002000897009_ST/images2.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022161600200089739/SYS201310221616002000897009_ST/images3.png)
D.
查看答案
王英同学从A地沿北偏西60°方向走100m到B地,再从B地向正南方向走200m到C地,此时王英同学离A地( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022161600200089739/SYS201310221616002000897008_ST/images0.png)
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022161600200089739/SYS201310221616002000897008_ST/0.png)
m
B.100m
C.150m
D.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022161600200089739/SYS201310221616002000897008_ST/1.png)
m
查看答案
有一边长为2的正方形纸片ABCD,先将正方形ABCD对折,设折痕为EF(如图①);再沿过点D的折痕将角A翻折,使得点A落在EF的H上(如图②),折痕交AE于点G,则EG的长度为( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022161600200089739/SYS201310221616002000897007_ST/images0.png)
A.4
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022161600200089739/SYS201310221616002000897007_ST/0.png)
-6
B.2
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022161600200089739/SYS201310221616002000897007_ST/1.png)
-3
C.8-4
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022161600200089739/SYS201310221616002000897007_ST/2.png)
D.4-2
查看答案