题目

对于向量a=(2,-2,3),b=(-4,x,2)，且a⊥b,则X等于 A. -1              B. 1             C.-2            D. 2 答案：A假设你叫陈丽,请用英语完成以下两个任务。请用there be句型描写你的房间里有什么物品。1._________________________________________________________2._________________________________________________________3._________________________________________________________4._________________________________________________________5._________________________________________________________