Y1

Y 1 = 1.58198 + 0.257926 X 1 0.05016 X 2 0.000177 X 3 0.028704 X 1 2 + 0.000483 X 2 2 + 0.000008 X 3 2 0.002267 X 1 X 2 + 0.00156667 X 1 X 3 0.000012 X 2 X 3 (3)

Y2

Y 2 = 16.6632 + 2.67398 X 1 0.318867 X 2 + 0.085675 X 3 0.500926 X 1 2 0.0253333 X 1 X 2 + 0.0268333 X 1 X 3 + 0.00470667 X 2 2 0.00124 X 2 X 3 0.000240833 X 3 2 (4)

Y3

Y 3 = 5.54418 0.536037 X 1 + 0.00286 X 2 0.00192833 X 3 + 0.0714815 X 1 2 + 0.000053 X 2 2 0.000019 X 3 2 0.002533 X 1 X 2 + 0.00203 X 1 X 3 0.000008 X 2 X 3 (5)

Y4

Y 4 = 0.878881 + 0.186537 X 1 + 0.0549 X 2 0.00486 X 3 0.101481 X 1 2 + 0.00373333 X 1 X 2 + 0.001233 X 1 X 3 0.000533 X 2 2 + 0.00006 X 2 X 3 + 0.000016 X 3 2 (6)

Y5

Y 5 = 66.0527 198.462 X 1 + 26.6765 X 2 5.203 X 3 0.723889 X 1 2 + 2.5676 X 1 X 2 + 0.4439 X 1 X 3 0.330872 X 2 2 + 0.000044 X 2 X 3 + 0.0233325 X 3 2 (7)

Y6

Y 6 = 60.0084 + 1.218 X 1 + 0.815993 X 2 0.00922833 X 3 + 0.115 X 1 2 0.0354667 X 1 X 2 + 0.00926667 X 1 X 3 0.006904 X 2 2 + 0.000572 X 2 X 3 0.0000795 X 3 2 (8)

Y7

Y 7 = 167.815 + 8.15278 X 1 3.01338 X 2 + 0.551525 X 3 0.536111 X 1 2 + 0.031656 X 2 2 0.0010575 X 3 2 0.0624 X 1 X 2 + 0.023 X 1 X 3 0.009276 X 2 X 3 (9)

Y8

Y 8 = 74.6532 + 0.2445 X 1 + 0.11616 X 2 0.005905 X 3 0.011667 X 1 2 0.002072 X 2 2 0.000281 X 3 2 + 0.012 X 1 X 2 0.0021 X 1 X 3 + 0.001272 X 2 X 3 (10)