A Mining Operation Needs to Separate Silver and Copper

A mining operation needs to separate silver and copper.You are to determine whether this separation can be accomplished by oxidizing the metals to Ag⁺ and Cu⁺, each one at a concentration of 0.15 M, and then precipitating one as the chloride salt without precipitating the other.What is the concentration of the Ag⁺ remaining in solution when CuCl begins to precipitate? (For AgCl, pK_sp =9.74.and for CuCl, pK_sp = 6.76.)

A) 1.57* 10^-2 M
B) 1.57 * 10^-4 M
C) 2.23 *10^-2 M
D) 2.23 -10^-4 M
E) 3.72* 10^-3 M