题目

Mr. Green is on time for everything. How ____ it be that he was late for the important meeting?  A.  should              B.   can               C. may                 D. must 答案：B如图，点A、B是双曲线y=上的点，分别经过A、B两点向x轴、y轴作垂线段，若S阴影=1，则S1+S2=    ．