唯物辩证法的否定之否定规律揭示了事物发展的( )。
A．方向和道路
B．形式和状态
C．结构和功能
D．源泉和动力
参考答案：A
正态分布有两个参数，它们是（）
A.平均值和方差s2
B.平均值和标准差s
C.均数μ和标准差σ
D.标准差s和变异系数CV
E.平均值和变异系数CV
—Could you please tell me ________?
—Sure. There's one near the bank. You can eat delicious food there. [ ]
A. where is the pay phone
B. is there a restaurant near here
C. where the pay phone is
D. if there is a restaurant near here
