135. Solving a chemistry problem

The solution of the paramagnetic salt Ni(NO3)2 (T=0.003314) was used as a titrant in the magnetic relaxation titration of 25.00 ml of the solution of the diamagnetic salt K4Fe(CN)6. Based on the results of titration, determine what mass (g) of K4Fe(CN)6 is contained in 200.0 ml of solutions 1,2,3:
Option 1
V Ni(NO3)2, ml 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00
A, standard units for solution 1 19.0 19.0 19.0 19.0 19.0 22.0 37.0 52.0 67.0