— I wonder if this smart phone is Mary's.— It _______ belong to her. _______ is totally different from this one.
A: mustn't; Her
B: can't; Her
C: can't; Hers
D:may; Hers
已知下列命题:①对角线互相平分的四边形是平行四边形;②等腰梯形的对角线相等;③对角线互相垂直的四边形是菱形;④内错角相等.其中假命题有( )
如图所示,在互相垂直的匀强电场和匀强磁场中,电荷量为q的液滴在竖直面内做半径为R的匀速圆周运动.已知电场强度为E,磁感应强度为B,则液滴的质量和环绕速度分别为( )
The place _____the bridge is supposed to be built should be _____the cross river traffic is
the heaviest.