The data in Table 12.2 represent the percent of impurities that resulted for various temperatures and sterilizing times during a reaction associated with the manufacturing of a certain beverage....

The data in Table 12.2 represent the percent of impurities that resulted for various temperatures and sterilizing times during a reaction associated with the manufacturing of a certain beverage. Estimate the regression coefficients in the polynomial model

y_i
=β
₀ +β
₁
x
_1i
+β
₂
x
_2i
+β
<sub>11

i</sub>
+β
<sub>22

i</sub>
+β
₁₂
x
_1i

x
_2i
+??

_i

,fori= 1,2, . . . ,18.

Table 12.2: