2. A researcher examines the strengths of a synthetic ber that may be affected by the percentage of cotton in the ber. Five levels of this percentage are considered, the data are in the table below: Percentage of Cotton Tensile Strength in 1b/i112 771511 1217121818 14 18 18 19 19 25 22 19 23 7 10 11 15 a) Are the differences in the mean breaking strengths due to the percentages of cotton used? Provide the 6-step procedure, use RR and p-value approaches. You can use Minitab to obtain the ANOVA table (instead of hand calculations of the table). b) WWW\" Use Minitab to create the boxplots for multiple comparisons, include the boxplots and comment on which means are the same, which are different and why. c) WWW Get the appropriate Tukey simultaneous condence intervals in Minitab, include the corresponding grouping information and the plot of the simultaneous CIs. Comment on which means are the same, which are different and why. 3. Refer to Problem 2. Are the differences in the mean breaking strengths due to the percentages of cotton used, if we only consider 15% and 20%? a) Can the true variances for the two populations be assumed equal? Use an appropriate interval to answer this question. b) Test for the difference in the true mean breaking strengths for 15% and 20% using the AN OVA method. Show all steps, and use RR and pvalue approach. c) Test for the difference in the true mean breaking strengths for 15% and 20% using the appropriate ttest method. Show all steps, and use RR, pvalue, and interval approaches