A11 Explain briefly what you understand by the term \"robust\" in the statement \"the semi interquartile range is a robust measure for the spread of a sample\". A12 Consider the following R session: > X x[1:2,] X6.18612839464861 X16.1439648602886 X.2.2661743111 1 -4.199269 -0.5049419 1.435955 2 6.777002 2.3319940 2.483453 X1.91989407626534 X.3.4849056122722 X.6.31258140805819 1 -1.934758 2.520748 3.242843 2 -3.852088 10.125005 -1.316922 What problem does the output indicate and how can the problem be fixed? A13 Determine all 40%quantiles of the sample 0.03, 0.181, 0.313, 0.353, 0.372, 0.419, 0.42, 0.543, 0.549, 0.572