Are there any boys in your class? - ______________
A:Yes, there is.
B:Yes, there are.
C:Yes, there was.
D:No, there weren't any.
将某样本数据分析整理后分成6组,且组距为5,画频数分布折线图时,从左到右第三组的组中值为20.5,则分布两端虚设组组中值为____ 和____ .
If someone spends his or her time, effort and money writing a book, for example, he or she deserves _______ for it.