题目

  ______ you are supposed to do ______ you don't like a thing is ______ it. Don't complain.     A. That; what; change                       B. When; that; to change      C. What; when;to change                     D. What; that; changing 答案：C如图所示的茎叶图记录了华润万家在渭南城区甲、乙连锁店四天内销售情况的某项指标统计：（I）求甲、乙连锁店这项指标的方差，并比较甲、乙该项指标的稳定性；（Ⅱ）每次都从甲、乙两店统计数据中随机各选一个进行比对分析，共选了3次（有放回选取）．设选取的两个数据中甲的数据大于乙的数据的次数为，求的分布列及数学期望