衡量样本平均值的离散程度错误的有()。
A、标准偏差
B、相对标准偏差
C、极差
D、平均值的标准偏差
参考答案:A,B,C
一 I'm sorry. That wasn't of much help.
一 Oh, _____. As a matter of fact, it was most helpful. [ ]
A. sure it was
B. it doesn't matter
C. of course not
D. thanks anyway
截至2011年,贵州被列入世界自然遗产地的有下列:()。
A、荔波
B、镇宁
C、遵义
D、赤水