题目

The bargain they reached with their employers was to reduce their wage claim________a shorter working week.A．in return for  B．in place of    C．in honour of  D．in charge of 答案：A 如图，在平面直角坐标系中，菱形OACB的顶点O在原点，点C的坐标为(4，0)，点B的纵坐标是－1，则顶点A的坐标是 [　　] A．(2，－1) B．(1，－2) C．(1，2) D．(2，1)