He said there was a great gap between the views expressed in the media and what ______ people were thinking.

A．usual

B．general

C．normal

D．ordinary

矩形线圈的匝数为50匝，在匀强磁场中绕垂直于磁场的轴匀速转动时，穿过线圈的磁通量随时间的变化规律如图所示，下列结论正确的是

A．在t=0.1 s和t=0.3 s时，电动势最大

B．在t=0.2 s和t=0.4 s时，电动势为零

C．电动势的最大值是157 V

D．在t=0.4 s时，磁通量变化率最大，其值为3.14 Wb/s