题目

下列说法中，正确的是（） A . —个游戏中奖的概率是 ，则做10次这样的游戏一定会中奖 B . 为了了解一批炮弹的杀伤半径，应采用全面调查的方式 C . 一组数据8，8，7，10，6，8，9的众数是8 D . 若甲组数据的方差是0.1，乙组数据的方差是0.2，则乙组数据比甲组数据波动小 答案：C听下面一段材料，回答第1-3题。 1. Who are these two speakers? [     ]A. Students. B. Teacher and student. C. Business partners. 2. Why, according to the man, do many American families have two phone lines? [     ]A. The children enjoy talking on the phone. B. Family members all need to use the phone. C. American families have a lot of business needs. 3. What can we learn about the woman? [     ]A. She agrees that telephones discourage reading and writing. B. She thinks telephones have both advantages and disadvantages. C. She has a positive attitude toward telephone.