题目

根据下列句子及所给汉语注释，在答题卡相应的位置上写出空缺处各单词的正确形式（每空只写一词） 71. His ___________（申请）to the company for manager has been refused. 72. As I ran up the stairs, my foot _________(滑到) and I fell. 73. Shanghai is the ___________(商业) heart of the country. 74. The main __________(反对) to the plan was that it would cost too much. 75. Don't always ___________(假定) the worst, something can be good. 76. At what age are children able to ___________(辨别) between right and wrong? 77. The ___________(如图所示，一导线弯成半径为a的半圆形闭合回路．虚线MN右侧有磁感应强度为B的匀强磁场．方向垂直于回路所在的平面．回路以速度v向右匀速进入磁场，直径CD始终与MN垂直．从D点到达边界开始到C点进入磁场为止，下列结论正确的是（ ）A．感应电流方向不变B．CD段直线始终不受安培力C．感应电动势最大值E=BavD．感应电动势平均值