What is the post condition of an expression or variable?

The ksp of srso4 is 3.2 × 10–7. what is the equilibrium concentration of sulfate ion in a 1.0-l solution of strontium sulfate to which 0.10 mol of sr(ch3co2)2 has been added? a. 3.2 × 10–8m b. 3.2 × 10–6m c. 5.7 × 10–4m d. 8.0 × 10–4m