题型:选择题 在一个暗箱里放有a个除颜色外其它完全相同的球,这a个球中红球只有3个。每次将球搅拌均匀后,任意摸出一个球记下颜色再放回暗箱。通过大量重复摸球实验后发现,摸到红球的频率稳定在25%,那么可以推算出a大约是( )A.12 B.9C.4 D.3 查看答案
题型:选择题 —Excuse me, Mr. Johnson,could you tell me ______? —Right on the table in the corner of the room. [ ]A. where I can buy a book of English B. when I can get to the book store C. how I can get to the book store D. where I can get my book of English 查看答案