选择题:A.n=2个,B=4.2m B.n=2个,B=3.5m C.n=4个,B=4.2m D.n=4个,B=1.8m 题目分类:公用设备师 题目类型:选择题 号外号外:注册会员即送体验阅读点! 题目内容: A.n=2个,B=4.2mB.n=2个,B=3.5mC.n=4个,B=4.2mD.n=4个,B=1.8m 参考答案: 答案解析: