An article in Fuel Processing Technology (Application of the Factorial Design of Experiments to Biodiesel Production from Lard, 2009, Vol. 90, pp. 14471451) described an

An article in Fuel Processing Technology (€œApplication of the Factorial Design of Experiments to Biodiesel Production from Lard,€ 2009, Vol. 90, pp. 1447€“1451) described an experiment to investigate the effect of potassium hydroxide in synthesis of biodiesel. It is suspected that potassium hydroxide (PH) is related to fatty acid methyl esters (FAME) which are key elements in biodiesel. Three levels of PH concentration were used, and six replicates were run in a random order. Data are shown in the following table.

(a) Construct box plots to compare the factor levels.

(b) Construct the analysis of variance. Are there any differences in PH concentrations at α = 0.05? Calculate the P-value.

(c) Analyze the residuals from the experiment.

(d) Plot average FAME against PH concentration and interpret your results.

(e) Compute a 95% confidence interval on mean FAME when the PH concentration is 1.2. 

PH concentration (wt. %) FAME concentration (wt. %) 84.3 84.5 86.5 86.7 86.9 86.9 0.6 89.3 89.4 88.5 88.7 89.2 89.3 0.9 90.2 90.3 88.9 89.2 90.7 90.9 1.2