关于标准差与标准误，以下说法正确的是A．标准误可用来估计医学参考值范围 B．标准差可
题型：单项选择题
问题：
关于标准差与标准误，以下说法正确的是
A．标准误可用来估计医学参考值范围
B．标准差可反映样本均数的变异程度
C．标准误可描述正态(近似正态)分布资料的频数分布
D．样本含量一定时，标准差越大，标准误越小
E．标准误是表示抽样误差的大小的指标
题型：单项选择题
根据图示和对话内容，在对话的空白处填上正确选项，使对话意义完整。
Kangkang: Michael. What's the __________(1)?
Michael: I have a __________(2) and I feel so painful. Kangkang: You should go and see a dentist now.
Michael: I think I just need a good rest. I __________ (3) the swimming game.
Kangkang: Maybe you ate much too sweets yesterday evening.
Michael: I see.
Kangkang: You should take care of yourself. After, the game you must __________(4) home at once,
and have __________(5).
Michael: OK. Thanks a lot. It's very kind of you!