Write the K expressions for:

A. 3S^-2 (aq) + 2Al⁺³ ➞ Al₂S₃ (s)

B. Ca⁺² + 2Ag (s) ➞ Ca (s) + 2Ag⁺¹ (aq)

C. C₃H₈ (g) + 5O₂ (g) ➞ 3CO₂ (g) + 4H₂O (l)