A chemical engineer is interested in the effects of reactant concentration (A) and reaction time (B) on the product. She performs four replicates of a 22 design, making the runs in random order. Following is the obtained experiment data with the final product weight (kg): Reactant Conc. (%) 25 40 Time (hr) 12 23, 22 28, 26 31, 34 33, 35 27, 31 27, 27 39, 36 38, 38 18 Please answer the following questions: (a) Draw a factor relationship diagram (sampling tree) of this experiment. (b) Estimate the factor effects (Please include the practical, graphical, and quantitative analyses). (c) Draw the AB interaction plot. Is the interaction strong or weak? (d) Develop a regression equation that could be used to predict product weight as a function of reactant concentration (A) and reaction time (B)