请教,这题目是啥意思阿...

在准备ＧＭＡＴ考试,看到这题目,根本没看懂题目的意思,请高手帮忙看下:

A researcher computed the mean,the median,and the standard deviation for aset of performance scores. If 5 were to be added to each score,which of these　three statistics would change?

a. the mean only
b . the median only
c.the standard deviation only
d.the mean and the median
e. the mean and the standard deviation

所有跟帖： 

• answer: D -I_am_nobody2- ♂ (0 bytes) () 12/06/2009 postreply 18:00:20

• 大概是D，标准方差变化应该很小。 -johnz002- ♂ (0 bytes) () 12/14/2009 postreply 14:25:33

• 回复：请教,这题目是啥意思阿... -davidmpang- ♂ (220 bytes) () 12/15/2009 postreply 21:39:00