8.Your data set contains a variable on region of residence that contains the following possible responses: Northeast, South, Midwest, West, and Pacific Coast.Which of the following measures of variability should you use for this variable?

a.Percentages

b.Interquartile range

c.Standard deviation

d.All may be used

9.A researcher wants to compare the safety scores of two groups of hospitals - for-profit and not-for-profit. The safety score is a composite measure that takes into account infection risks, surgical errors, occurrence of other bodily harm attributable to interventions, etc, with a potential range of 0 to 100.To analyze her results, what would be the most appropriate statistic?

a.Independent samples t-test

b.Dependent samples (paired) t-test

c.Oneway ANOVA

d.Chi-square