在比例尺为1:5000的地图上,量得甲,乙两地的距离25cm,则甲,乙的实际距离是 [ ]
A.1250km
B.125km
C.12.5km
D.1.25km
答案:D
What about__________ tomorrow?
A.go swimming
B.going swim
C.go to swim
D.going swimming
为什么有的聚合物热稳定性好,而有的热稳定性差?举例说明。