96. Solving a chemistry problem

4. A sample of biological material weighing 35.0 mg was processed and 20.0 ml of an alkaline solution containing bilirubin (Mr = 584.67 g/mol) was obtained. The diffusion current for cathodic reduction of bilirubin was measured to be 0.50 μA. 5.0 ml of a standard solution of bilirubin with a concentration of 5.0*10-4 mol/l was added to the solution. The height increase was 1.03 μA. Calculate the concentration (mg/kg) of bilirubin in the sample of biological material.