题目

设变量满足约束条件：的最大值为          （    ）        A．10     B．8       C．6       D．4 答案：CMrs.Green wants to buy that kind of cloth because she that the cloth very well. 　　A.has been told; washed B.has told; washes 　　C.has been told; is washed D.is told; is washed