《江城子·密州出猎》作者是____朝____(姓名)字____,号____,与____、____并称“三苏”。“江城子”是____,____是词的题目。
①小磁针的指向满足如图所示方向;
②滑动变阻器的滑片向右端移动后,通电螺线管的磁性减弱;
③原有导线不得更改.
—I've been working on a research report, which was ________ easy. Which of the following can't be put in the blank?
A.一种 B. 两种 C. 三种