9. (8 points) It is important to study the effect of the concentration of the reactant and the feed rate on the viscosity of the product from a chemical process. Let the reactant concentration be factor A, at levels 15% and 25%. Let the feet rate be factor B; with levels 20 Ib/hr and 30 lb/hr. The experiment involves two experimental runs. The average viscosity readings are in the table below Assuming a model containing two main effects and an interaction, calculate the main effects. Do you have any interpretations at this point