The following table contains casting strength is to be optimized for the casting time (A, 40-60 s) and temperature (B, 200-260C). First 4 are points are factorial, next 4 axials and last 5 are central points. Run A B 1 2 3 4 5 8 9 10 6 7 60 50 43 57 57 40 50 50 50 43 209 209 251 251 230 230 200 260 230 230 250 380 190 420 330 Strength 210 280 365 420 11 12 13 50 50 50 230 230 230 335 340 335 335 Q.11 Code Factor A and B. Q.12 Obtain the estimate of error. Q.13 Check for Interactions. Q.14 Check for quadratic effect. Q.15 Use the fitted equation and optimize the response. Q.16 Draw the response curve.