题目

已知O是坐标原点，点A（﹣1，1）．若点M（x，y）为平面区域上的一个动点，则的取值范围是 ． 答案：[0，2]听下面一段材料, 回答第1至3 题.        1. What had gone wrong in their house?A. Their washing machine    B. The electricity.      C. The lights.2. Which of the following is true?A. Mr. Black did nothing for them at all.    B. Mr. Black asked too much money from them for his work.    C. Mr. Black did help them but couldn't solve the problem completely that day.  3. Why did the man think it would cost him dearly?  A. Because he wanted to buy a car.      B. Because he didn't have a good job.    C. Because their car needed repairing.