15. Consumer Safety Institute wishes to compare flammability of 3 fabrics used in making dolls. Burn time (how long a fixed-size piece of the material burned after coming in contact with the flame) in seconds is recorded for 3 samples of each fabric. The data are given below along with the corresponding computer output. \begin{tabular}{lccc} Fabrics & Mean & Std. dev. & $n$ \hline 1 & $17.17$ & $1.85$ & 3 2 & $12.80$ & $2.60$ & 3 W 3 & $12.83$ & $2.05$ & 3 \end{tabular) A computer printout for this problem is below. ANALYSIS OF VARIANCE $\begin{array}{lcrrcc}\text { Source } & \text { df } & \text { Sum of Squares } & \text { Mean Square } & \text {F} & \text { P}\\\text { Factor } & 2 & 37.846 & 18.923 & 4.857 & 0.0557 \text { Error } & 6 & 23.373 & 3.896 && \ \text { Total } & 8 & & & & \end{array}$ a) State the null and alternative hypotheses for this ANOVA $F$ test. [2 points] Using a $5 \%$ significance level, test the hypotheses in part (a). Make sure to check the requirements. [5 points] CS.VS. 1269|