根据《烟花爆竹安全级别、类别和标识标注》(DB11/358—2011)规定,北京市允 发布时间:2019-07-29 23:52 │ 来源:www.tikuol.com 题型:单项选择题 问题: 根据《烟花爆竹安全级别、类别和标识标注》(DB11/358—2011)规定,北京市允许销售和燃放的组合烟花类产品单发装药量应≤()克。A.5B.10C.15D.20
题型:单项选择题 If a three-digit number is selected at random from the integers 100 to 999, inclusive, what is the probability that the first digit and the last digit of the integer will both be exactly two less than the middle digit ?()A. 1:900B. 7:900C. 9:1,000D. 1:100E. 7:100 查看答案