For the following sample (3.27 -1.24 3.97 2.25 3.47 -0.09 7.45 6.2 3.74 4.12 1.42 2.75 -1.48 4.97 8 3.26 0.15 -3.64 4.88 4.55) form a 0.95 confidence interval for mu assuming that this is a sample from an N(mu, sigma²) distribution.

Also compute a 0.95 confidence interval for mu based on the sign statistic, a bootstrap t confidence interval and a bootstrap percentile 0.95 confidence interval using m = 10³