Answer Happy

An experiment was conducted to determine the effect of pressure
and temperature on the performance of a chemical. Two levels of
pressure (in pounds per square inch, psi) and three levels of
temperature were used:
Pressure (psi)
Temperature (F)
50
100
80
200
300
A run of the experiment at each temperature-pressure combination
resulted in the data shown in the following table:
Performance
Pressure (psi)
Temperature (F)
21
50
100
23
50
200
26
50
300
22
80
100
23
80
200
28
80
300