Suppose that the data set {x
1, x
2, x
3, ..., x
N} has median M and interquartile range IQR. If M' and IQR' are the median and interquartile range of the data set

respectively, then
◦ M' = M, and IQR' = IQR + c.
◦ M' = M + c, and IQR' = IQR + c.
◦ M' = M + c, and IQR' = IQR.
◦ M' = M, and IQR' = IQR.
◦ none of these