10 g of Ca-saturated smectite (CEC = 100 meq/100 g) is mixed with water containing 1*10-3 mol/L Ca and 1*10-3 mol/L Cd. The exchange reaction is: Cd2+ + Caclay = Ca2+ + Cdclay The selectivity coefficient (K) = 0.9. Calculate the amount of Cd2+ in solution after equilibrium has been attained.