1.25 the following data set is related to that in exercise 1.24. it gives the percentages of the families that are in the upper income level, for the same individual schools in the same order as in exercise 1.24. 72.2 31.9 26.5 29.1 27.3 8.6 22.3 26.5 20.4 12.8 25.1 19.2 24.1 58.2 68.1 89.2 55.1 9.4 14.5 13.9 20.7 17.9 8.5 55.4 38.1 54.2 21.5 26.2 59.1 43.3 (a) calculate the sample mean. (b) calculate the sample median. (c) construct a relative frequency histogram of the data. (d) compute the 10% trimmed mean. compare with the results in (a) and (b) and comment.