A:﹣2x5
B:2x5
C:﹣2x6
D:2x6
A traffic accident happened this morning. ____ (luck), no one was badly hurt.
如图所示,电压表能测L1灯两端电压的是( )
若m是方程x2﹣2x=2的一个根,则2m2﹣4m+2010的值是 ____.