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问题 解答题

甲、乙两支篮球队进行比赛，已知每一场甲队获胜的概率为0.6，乙队获得的概率为0.4，每场比赛均要分出胜负，比赛时采用三场两胜制，即先取得两场胜利的球队胜出．

（Ⅰ）求甲队以二比一获胜的概率；

（Ⅱ）求乙队获胜的概率；

答案

（Ⅰ）根据题意，若甲队以二比一获胜，

即前两场中甲胜1场，第三场甲获胜，

其概率为P1=（C21×0.6×0.4）×0.6=0.288；

（Ⅱ）乙队以2：0获胜的概率为P′2=0.4×0.4=0.16；

乙队以2：1获胜的概率为P″2=C210.4×0.6×0.4=0.192

∴乙队获胜的概率为P2=0.42+C21×0.4×0.6×0.4=0.16+0.192=0.352．

选择题

— _____________?

— No, Shen Jun isn't here.[ ]

A. Who isn't here 

B. Is everyone here

C. Is Shen Jun there

D. Is student here
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单项选择题

I will always remember my mother’s last few days in this world.

On February 14th, 2000, my class went on a field trip to the beach. I had so much fun. When we returned to school, my teacher told me to go to the headmaster’s office. When I got into the office, I saw a police officer. Suddenly I realized something was wrong. The police officer told me what had happened and we went to pick my sister up. After that, we went to the hospital and waited. Time went slowly. Finally, we got to see our mother. It was terrible.

On the next day, the headmaster came and told my two teachers what had happened. I was taking a rest that day. I knew it had something to do with my mother. I kept thinking that she either died or had gotten better. How I wished that she had gotten better. When my teacher took me outside, my sister ran up to me. She started crying, "She’s gone. Teresa, mommy’s gone. She’s dead. " I couldn’t believe it. We jumped into the car and drove straight to the hospital. Most of my family were there. The silence was terrible. I knew I had to say goodbye.

Today when I look back, I still miss my mother very much, but I know that I will live. My mother was a p mother, who had the biggest heart. My mother was an angel walking on the earth. I will always remember her as living. When someone is asked who their hero is, they usually say someone famous, like Michael Jordan or Britney Spears. When someone asks me who my hero is, I tell them, my mother. My mother lives every day. That is what makes her at rue hero.

Where was the writer when she learned her mother was very ill().

A．On the beach.

B．At the hospital.

C．At school.

D．At home.
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