问题:
A.0.3B.0.595C.0.7D.0.795
参考答案:C
参考解析:
答案:C解析:分情况讨论:1、甲胜3场:0.7×0.5×0.7=0.245,2、甲胜2场:0.7×0.5×0.3×2+0.7×0.5×0.7=0.455,所以总的概率=0.7