3. Solving a chemistry problem

3. The absorption coefficients of components A and B in solution at λ=540 nm are, respectively, eλ(A)=574 l/mol*cm, eλ(B)=428 l/mol*cm. The optical density of a solution containing both of these components was found to be 0.36. What is the concentration of B in this solution if [A]=5*10-4 mol/l at l=1.0 cm.