Table 1.

Experimental central composite design matrix and its response and predicted value.

Run	Experimental Variables			Response Y (mm)
	P	R	C(g/L)	Expt.	Predicted
1	11.00	3.00	1.00	16.7	16.60
2	9.00	1.00	0.50	5.9	5.91
3	11.00	3.00	1.00	17	16.60
4	11.00	3.00	1.00	16.5	16.60
5	11.00	3.00	1.84	15.8	15.57
6	9.00	5.00	1.50	10.3	10.44
7	11.00	−0.36	1.00	3.1	3.02
8	13.00	5.00	1.50	14.6	14.69
9	13.00	1.00	0.50	8.3	8.27
10	13.00	5.00	0.50	11	11.37
11	7.64	3.00	1.00	5.1	5.44
12	11.00	3.00	0.16	13.2	13.26
13	11.00	6.36	1.00	10	9.91
14	9.00	5.00	0.50	9.2	8.82
15	11.00	3.00	1.00	16.4	16.60
16	11.00	3.00	1.00	16	16.60
17	14.36	3.00	1.00	11.5	10.99
18	9.00	1.00	1.50	5.6	5.34
19	13.00	1.00	1.50	8.9	9.39
20	11.00	3.00	1.00	17	16.60