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8. Listed below are speeds (mi/h) measured from southbound traffic on 1-280 near Cupertino, California. This simple random sample was obtained at 3:30 p.m. on a weekday. Use the sample data to construct a 90% confidence interval estimate of the population standard deviation. Does the confidence interval describe the standard deviation for all times during the week? 62 61 61 57 61 54 59 58 59 69 60 67