题目

Is it the country__________you studied__________you are going to visit next week?    A. in which; which     B. where; that     C. that; that  D. which; that   答案：B在某一试验中事件A出现的概率为，则在次试验中出现次的概率为（  ） A．1－                               B． C．1－                           D．