题型:问答题 简答题 The lead singer was ill and couldn't sing that night, and her ________ didn't perform well, which made the audience disappointed.[ ]A.agent B.attitudeC.substitute D.institute 查看答案
题型:问答题 简答题 如图所示,相距为d的两条水平虚线L1、L2之间是方向水平向里的匀强磁场,磁感应强度为B,正方形线圈abcd边长为L(L<d),质量为m,电阻为R,将线圈在磁场上方高h处静止释放,cd边刚进入磁场时速度为v0,cd边刚离开磁场时速度也为v0,则从线圈cd边刚进入磁场起一直到ab边离开磁场的过程中( )A.感应电流所做的功为mgdB.感应电流所做的功为2mgdC.线圈的最小速度可能为mgRB2L2D.线圈的最小速度一定为2g(h+L-d) 查看答案
题型:问答题 简答题 毛细胞型星形细胞瘤的典型MRI表现()。A.小脑半球或蚓部囊性或囊实性肿块B.实性成分T1WI低或等信号,T2WI等或稍高信号C.囊性部分T2WI高信号,FLAIR高信号D.呈不均匀明显强化E.Cho峰增高,NAA峰降低,乳酸峰增高 查看答案