66. Solving a chemistry problem

25(2) A portion of margarine weighing m, g was dissolved in a flask with a capacity of 50.00 cm3. Aliquots of 20.00 cm3 were taken into two volumetric flasks with a capacity of 50.00 cm3. A solution containing 0.00100 g of Ni was added to one flask. A solution of dimethylglyoxime was placed in both flasks and the solutions were made up to the mark.
Calculate the mass fraction of Ni in margarine if the following data were obtained during photometry of solutions
Option 2
m, g 4.8280
D 0.190
Dx st 0.410