A 50.0 mL sample containing Cd 2 + and Mn 2 + was treated with 58.6 mL of 0.0400 M EDTA . Titration of the excess unreacted EDTA required 13.0 mL of 0.0280 M Ca 2 + . The Cd 2 + was displaced from EDTA by the addition of an excess of CN − . Titration of the newly freed EDTA required 28.6 mL of 0.0280 M Ca 2 + . What are the concentrations of Cd 2 + and Mn 2 + in the original solution