Design of experiments; Doehlert method used.<br><p>2 factors (X1, X2); 7 trials; Y: responses.<br>
Matrix of the trials:<br><b>X1</b> - <b>X2</b><br>
25 - 180<br>
35 - 180<br>
15 - 180<br>
30 - 206<br>
20 - 206<br>
30 - 154<br>
20 - 154<br></p>
Estimated response surface; Y estimated for a 95% confidence level.
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