图上距离3厘米表示实际距离180千米,这幅图的比例尺是______.
180千米=18000000,
3:18000000=1:6000000.
故应填:1:6000000.
_____ is known to us all is that the 2008 Olympic Games will take place in Beijing. [ ]
A. It
B. What
C. As
D. Which
“三懂三会”错误的是()
A.懂设备结构,会使用
B.懂设备性能,会维修
C.懂设备原理,会排除故障
D.懂设备性能,会使用