机车每列拉车数量必须（）组列。
A、按规定
B、按产量
C、按工资
参考答案：A
_____ day has passed since she wentaway. [ ]
A. A great many
B. A good many
C. Many a
D. So many
博弈论认为博弈关系的类型大体有（）
A.负和博弈
B.囚徒博弈
C.正和博弈
D.斗鸡博弈
E.零和博弈
