The fluorescence of each of a series of acidic solutions of quinine was determined five times. The results are given below.
Concentration, ng ml-1
|
0
|
10
|
20
|
30
|
40
|
50
|
Fluorescence intensity
|
4
|
22
|
44
|
60
|
75
|
104
|
(arbitrary units)
|
3
|
20
|
46
|
63
|
81
|
109
|
|
4
|
21
|
45
|
60
|
79
|
107
|
|
5
|
22
|
44
|
63
|
78
|
101
|
|
4
|
21
|
44
|
63
|
77
|
105
|
Determine the slopes and intercepts of the un-weighted and weighted regression lines. Calculate, using both regression lines, the confidence limits for the concentrations of solutions with fluorescence intensities of 15 and 90 units. Compare the results of the unweighted regression to those of weighted regression.