| Factor |
Levels used, Actual (Coded)
|
| |
Low (-1) |
Medium (0) |
High (+1)
|
|
Independent variables
|
|
|
X1= FC-reagent (ml)
|
1.00 (-1) |
5.50 (0) |
10.00 (+1)
|
|
X2= Sodium carbonate (ml)
|
1.00 (-1) |
5.50 (0) |
10.00 (+1)
|
|
X3= Drug concentration (µg ml-1)
|
4.00 (-1) |
20.00 (0) |
36.00 (+1)
|
|
Constraints
|
| Dependant variables |
Y1=Absorbance
0.200 ≤ Y1 ≥0.872 |
|