The Equilibrium Constant for the Reaction C₇H₁₅COOH(aq) + HCOO^-(aq) $\leftrightharpoons$ C₇H₁₅COO^-(aq) + HCOOH(aq)
Is 7

The equilibrium constant for the reaction C₇H₁₅COOH(aq) + HCOO^-(aq) $\leftrightharpoons$ C₇H₁₅COO^-(aq) + HCOOH(aq)
Is 7.23 * 10^-2 at 25 ^$\circ$ C. If K_a for formic acid (HCOOH) is 1.77 * 10^-4, what is the acid dissociation constant for C₇H₁₅COOH

A) 2.45 * 10^-3
B) 4.08 * 10^-2
C) 7.81 * 10^-4
D) 1.00 * 10^-4
E) 1.28 * 10^-5