A manufacturing process with two process variables (x1,x2) is often described by the empirical model: y=bo +bqxq+byx2+b12XqXq+b3x2q+bax?> Such a model is often used because: None of the shown options. It often provides reliable predictions outside of the experimental test conditions for variables xq and X2: It has clear theoretical foundations for all manufacturing processes. It often provides reliable predictions within the range of the experimental test conditions for variables x and X2