26. Solving a chemistry problem

24.2 To build a calibration graph, 5.00 8.00 10.00 ml of a solution of iron ammonium alum with T (Fe) = 0.0000500 was placed in flasks with a capacity of 50.00 ml, hydrochloric acid was added to potassium thiocyanate, brought to the mark with water and measured optical density at 496 nm:
U, ml 5.00 8.00 10.00
A, 0.365 0.595 0.750
The test solution containing iron and nickel was diluted in a 100.00 ml flask, two 20.00 ml aliquots were taken into 50.00 ml flasks. One sample was diluted to the mark with water, HCl, KSCN were added to the second sample and also brought to the mark with water. The optical density of the first sample at 496 nm is A Ni=0.080. The optical densities of the second sample for different variants are equal
Option 2
0.530