QUESTION
RightAid Inc. operates a regional chain of 120 pharmacies. Each pharmacy's floor plan includes a greeting card department which is relatively isolated. Cathy Eng, Marketing Manager, feels that the level of lighting in the greeting card department may affect sales in that department. She chooses three levels of lighting (soft, medium, and bright) and randomly assigns six pharmacies to each lighting level. Analysis of Cathy's data yielded the following ANOVA table: \begin{tabular}{|c|c|c|c|c|} \hline Source of Variation & SS & df & MS & $F$ \\ \hline Treatment & 49411.11 & 2 & 24705.56 & 10.4304 \\ \hline Error & 35529.17 & 15 & 2368.611 & \\ \hline Total & 84940.28 & 17 & & \\ \hline \end{tabular} Using $a=0.05$, the appropriate decision is do not reject the null hypothesis $\mu_{1} \leq \mu_{2} \leq \mu_{3}$ reject the null hypothesis $\mu_{1} \neq \mu_{2} \neq \mu_{3}$ reject the null hypothesis $\mu_{1}=\mu_{2}=\mu_{3}$ do not reject the null hypothesis $\mu_{1} \geq \mu_{2} \geq \mu_{3}$ inconclusive