m2表示2个m相乘。
正确
The people in theearthquake-struck area didn't ____ despite the heavy loss oflives and property. [ ]
A. lose heart
B. break heart
C. take heart
D. put down heart
社会保险系统,是属于()模式的电子政务。
A、GtoG
B、GtoB
C、GtoC
D、GtoE