题目

How many men does your uncle _____ for him? A. have worked       B. have to work      C. have working     D. have been working   答案：C如图，两条宽都为1的纸条交叉重叠地放在一起，且它们的夹角为，则它们重叠部分的面积为    (        ) A．           B．           C．            D． 1