柱面坐标机器人主要用于重物的（）等工作。
A、装卸
B、分类
C、搬运
D、检测
参考答案：A, C
Recently I bought an ancient Chinese knife,__________was reasonable.
A．which price
B．the price of which
C．its price
D．the price of that
联合国教科文组织机构在哪？
