There ______ many bikes in the streets ten years ago. [ ]
A. was
B. is
C. are
D. were
答案:D
适用于未分组的分布数列的是( )。
A.加权算术平均数 B.简单调和平均数C.加权几何平均数 D.加权调和平均数
在MMPI的临床量表中,英文缩写( )代表轻躁狂。
A.D
B.Hs
C.Ma
D.Sc