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；
（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．
任务型读写(共10小题；每小题1分，满分10分) 阅读下面短文，根据所读内容在表格中的空白处填入恰当的单词。注意：每个空格只填一个单词。 Clean air is only made up of nutrition, oxygen and water. Our country has been industrialized; our cities have grown and traffic has increased.. For these reasons there has come an increase in the number of by-products released into the air, such as particles from burning fuels and poisonous gases from chemical reactions. These gases become pollutants. Air pollution has a bad effect on the earth and our environment. Air pollution can result in acid rain, and it can also lead to the Greenhouse Effect---a condition in which pollution stops radiation from travelling out of the earth’s atmosphere. This upset of the natural ranges. Due to the Green Effect, the temperature on the earth becomes warmer, which is known as Global Warming. What’s more, air pollution may produce holes in the ozone layer---this layer of ozone naturally keeps ultraviolet rays of the sun from reaching the earth. The holes make it possible for the rays to reach us. Don’t let all the bad news about air pollution get you down because there are many ways to help fight the air pollution. Every one of us can employ a variety of solutions to air pollutions to air pollution. A smoker can give up smoking. While shopping, you can choose organic and natural products .Driving less and carpooling more can also contribute to less pollution. Next time, keep your air-conditioning low. Of course you can plant more trees. Air pollution is a major problem for our planet .However, as long as we realize how serious the air pollution is and take action now, everyone can make a difference. Title:Air 71____________
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